with open ("n38bn.txt", r, encoding="utf-8") as file: # Open the file for the length of the width block numbers = [float (line.strip ()) for line in file] # For each line, strip, convert to float and add to list result = sum (numbers) # Sum the list print ("The sum is", result) This uses a list comprehension to build the list in one line, and ...In: merged['platnosc_total'].astype(float) Out: ValueError: could not convert string to float: '7,50' Does this mean that the rest got converted, and only the row with 7,50 is the cause? How can I actually cast this field/column to float?ValueError: could not convert string to float: 'D' I have tried: train=train.astype(float) Replacing all 'D' with another value. train.convert_objects(convert_numeric=True) But the issue still persists. I also tried printing all the valueErrors in my csv file, but cannot find a reference to 'D'. This is my trace:Maybe I should use other module to read CSV. I tried pandas right now, and it reads just fine as anyone would have expected, but OTOH I don't want to load huge package just to read CSV to array, and don't use it again... Nov 26, 2018 · ValueError: could not convert string to float: 'New York'. I read the answers to similar questions and then opened scikit-learn documentations, but how you can see scikit-learn authors doesn't have issues with spaces in strings. I know that I can use LabelEncocder from sklearn.preprocessing and then use OHE and it works well, but in that case. Like the comments said, you are trying to convert a string or object (in this case "Male") into a float. Try to output your variables and their types to makes you see where you are trying to convert the float.with open ("n38bn.txt", r, encoding="utf-8") as file: # Open the file for the length of the width block numbers = [float (line.strip ()) for line in file] # For each line, strip, convert to float and add to list result = sum (numbers) # Sum the list print ("The sum is", result) This uses a list comprehension to build the list in one line, and ...Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about TeamsThough not the best solution, I found some success by converting it into pandas dataframe and working along. code snippet # convert X into dataframe X_pd = pd.DataFrame(data=X) # replace all instances of URC with 0 X_replace = X_pd.replace(' ',0, regex=True) # convert it back to numpy array X_np = X_replace.values # set the object type as float ...You're getting this because your series is string, but it contains some NAs, which actually get represented in pandas as nan, which is a float value (that's how pd.read_csv() will handle it). That's why pandas gives a strange warning claiming the string series is a float: Solution: first, fill any NA values in your string column with empty-string:May 26, 2014 · 1. I'm trying to build a simple program using tkinter and I want to assign the value that the user enters into an entry widget as a float variable, not a string. Here is my code: from tkinter import * root = Tk () x_entry = Entry (root) x_entry.pack () x_string=x_entry.get () def enter_click (event): x=float (x_string) print (x) enter_button ... Jul 21, 2019 · 5,534 3 25 36. asked Jul 21, 2019 at 14:51. Sudhanshu Kumar Tiwari. 1 1. 1. Somehow you are trying to convert the string 'f' to a float.It is probably in the .csv file. You'll have to find it and figure out why. – wwii. Dec 2, 2017 · 2. You're trying to convert the string "" into a float. "" doesn't make sense as a float, so you'll have to do one of the following. 1 Populate your fields with strings that make sense as floats. For example "0". 2 Set a default value. The following code sets wins as the float value of wins or 0.0 if not applicable. ValueError: could not convert string to float. Now, i know it is a string but how can i convert it into a tuple type that can be read in the function, as the value contains commas and cannot be converted to float i think. the function takes in a tuple of three numbers separated by commas (RGB values) and returns the color Closet to it. MY CODE:If you want to improve your model it is even recommended to normalize your model between -1;1 in general and therefore to use decimal numbers, hence the expectation of a float. In your case, your dataframe seems to contain exclusively string entries. As Dilara Gokay said, you first need to transform your strings into floats and to do so, use ...Python "ValueError: could not convert string to float: %". Create a function called format_change which takes a string such as those in the Change column and does the following: def format_change (string): if string [-1] == "%": string = string [-1] str_as_float = float (string) if str_as_float > 0: str_as_float = str_as_float * 100 return str ... Now, if you enter a string, this is how the output would look: Enter a number (precision up to at least one decimal place)= Hello Please enter a number as per instruction! And, if we give a proper float input, the output would be: Enter a number (precision upto atleast one decimal place)= 16.663 After dividing by 10 we get= 1.6663000000000001.ValueError: could not convert string to float: 'Null' # else, only a single dtype is given # _astype_nansafe works fine with 1-d only # TODO(extension) # Explicit copy, or required since NumPy can't view from / to object. Jun 22, 2023 · When I try to replicate this behavior, the corr() method works OK but spits out a warning (shown below) that warns that the ignoring of non-numeric columns will be removed in the future. Aug 23, 2023 · STILL GOT QUERIES? Get a Live FREE Demo. Explore the trending and niche courses and learning maps; Learn about tuition fee, payment plans, and scholarships; Get access to webinars and self-paced learning videos Aug 3, 2022 · This tutorial was tested with Python 3.9.6. Using the float() function. We can convert a string to float in Python using the float() function. This is a built-in function used to convert an object to a floating point number. Internally, the float() function calls specified object __float__() function. Example ValueError: could not convert string to float. Now, i know it is a string but how can i convert it into a tuple type that can be read in the function, as the value contains commas and cannot be converted to float i think. the function takes in a tuple of three numbers separated by commas (RGB values) and returns the color Closet to it. MY CODE:Jun 10, 2018 · ValueError: could not convert string to float: 'Yes, policy' while fitting to my Logistic Regression Model 0 What is causing this ValueError: could not convert string to float: '' while using logisticRegr.fit(x_train, y_train) – Replace the Unwanted Characters Using a Python Function. You can replace unwanted characters from your string using the “replace()” function. This will work for our previous pandas example, and the following string in our first example: “22,2.329%”. May 26, 2014 · 1. I'm trying to build a simple program using tkinter and I want to assign the value that the user enters into an entry widget as a float variable, not a string. Here is my code: from tkinter import * root = Tk () x_entry = Entry (root) x_entry.pack () x_string=x_entry.get () def enter_click (event): x=float (x_string) print (x) enter_button ... How to fix these errors . There are 4 methods to fix this issue. Those are: Remove all characters, and symbols, and extract only the number (using re) Remove leading and trailing unwanted characters (using `str.strip`) Replace the unnecessary character (s) with an empty string (using `str.replace`) Using try-catch logic.Fix ValueError: could not convert string to float. Solution 1: Ensure the string has a valid floating value. Solution 2: Use try-except. If you convert a string object into a floating-point in Python many times you will get a ValueError: could not convert string to float. Usually, this happens if the string object has an invalid floating value ...You input a value (or more) and it predicts another. A float is a number with decimals. For example, a 2 is an integer and a 2.53 is a float. What you can do is. a = '0.67687980' print (float (a)) Which returns. 0.67687980. However, you cannot do it with a string. a = 'Some string' print (float (a))now you have a full dataset with int and float and your SVC can works well with it but before you need to split: it is a good ideas to have a test size inferior to the train size , it may be preferable to use a value inferior to 0.5 for test_size find more about training set and test set size herePython: Naive Bayes fit function gives TypeError: float() argument must be a string or a number 0 ValueError: bad input shape (1, 4) in sklearn.naive_bayes.GaussianNBApr 25, 2015 · A solution to your question might be splitting the strings to represent two floating point numbers and then multiply them together, like in the following snippet: from sys import stderr callback = lambda x: stderr.write ('Invalid floating point number found: {0}'.format (x)) def convert (src, error_callback): ret = list () for item in src ... Jul 26, 2023 · Here, we first created an empty string in Python and then had to loop over the string with commas, apply the conditional statement to remove the commas, and then convert the resultant string into a float in Python. The output is: 2999.99 <class 'float'>. This way, we can use the Naive method to convert string with comma to float in Python. ValueError: could not convert string to float: RahulSingh: 3: 3,566: Apr-09-2020, 02:59 PM Last Post: dinesh : convert a list of string+bytes into a list of strings (python 3) pacscaloupsu: 4: 9,853: Mar-17-2020, 07:21 AM Last Post: markfilan : Convert dataframe string column to numeric in Python: darpInd: 1: 1,974: Mar-14-2020, 10:07 AM Last ...May 25, 2023 · Now, if you enter a string, this is how the output would look: Enter a number (precision up to at least one decimal place)= Hello Please enter a number as per instruction! And, if we give a proper float input, the output would be: Enter a number (precision upto atleast one decimal place)= 16.663 After dividing by 10 we get= 1.6663000000000001. Solution 2: Using str.replace () Function. The “ str.replace () ” function is also used to fix the “ ValueError: could not convert string to float ” by replacing any symbols or characters with an empty string. In the below snippet, the “ str.repalce () ” function is used to replace the unwanted symbols and strings:This article is aimed at providing information about converting the string to float. In Python, we can use float () to convert String to float. and we can use int () to convert a String to an integer. Input: "33.28" Output: 33.28 # float Explanation: int in input and float in output.This tutorial was tested with Python 3.9.6. Using the float() function. We can convert a string to float in Python using the float() function. This is a built-in function used to convert an object to a floating point number. Internally, the float() function calls specified object __float__() function. ExampleSolution 2: Using str.replace () Function. The “ str.replace () ” function is also used to fix the “ ValueError: could not convert string to float ” by replacing any symbols or characters with an empty string. In the below snippet, the “ str.repalce () ” function is used to replace the unwanted symbols and strings:In: merged['platnosc_total'].astype(float) Out: ValueError: could not convert string to float: '7,50' Does this mean that the rest got converted, and only the row with 7,50 is the cause? How can I actually cast this field/column to float?To convert string to float in Python, you can use the “float()” function. Pass the string you want to convert as an argument to the float() function, and it will return the float value. SyntaxHow to fix these errors . There are 4 methods to fix this issue. Those are: Remove all characters, and symbols, and extract only the number (using re) Remove leading and trailing unwanted characters (using `str.strip`) Replace the unnecessary character (s) with an empty string (using `str.replace`) Using try-catch logic.The “ValueError: could not convert string to float:<>” is an exception that is raised when we attempt to convert a string that cannot be converted into float using the float() function, for example, an empty string and a string with non-numeric characters.ValueError: could not convert string to float: 'X_train' ... not able to convert string to float in python and how to train the model with this dataset. 5.Let me clarify: The only table per file consists of four columns (time, temperature, humidity, dewpoint) and at some point (spanning roughly line 25 to 150 or so), only the value of humidity apparently is set to "--327", which python tries to convert to float and obviously fails to do.Dec 19, 2008 · You can simply do this by. s = '542.22' f = float (s) # This converts string data to float data with a decimal point print (f) i = int (f) # This converts string data to integer data by just taking the whole number part of it print (i) For more information on parsing of data types check on python documentation! Share. We can use data types like int, float, string, list, set… in our applications. When using different types of variables, it may be necessary to convert these to different types. Just like the str () function, Python also offers a handy built-in function that takes an object of type String as an argument and returns the corresponding Float object.The “ValueError: could not convert string to float:<>” is an exception that is raised when we attempt to convert a string that cannot be converted into float using the float() function, for example, an empty string and a string with non-numeric characters.I keep getting a valueerror: could not convert string to float: '1956-01' The code is supposed to scale the data for machine learning using minmax scaler, but its saying I have strings. I think the code converted it into datetime. Oct 26, 2019 · Yes, this is exactly the error message that I have got: ValueError: could not convert string to float: XXX. But I didn't see any space in cells "XXX", "YYY", and "ZZZ" in excel as I manually entered them. I double checked by using "find and replace" to remove extra space between words, but see the message "we couldn't find anything to replace". Jul 21, 2019 · 5,534 3 25 36. asked Jul 21, 2019 at 14:51. Sudhanshu Kumar Tiwari. 1 1. 1. Somehow you are trying to convert the string 'f' to a float.It is probably in the .csv file. You'll have to find it and figure out why. – wwii. Syntax. Python has different data types for a different set of values, Integers deals with numbers and float deals with both decimal and numeric characters, Boolean deals with Binary values ( True or False) and there are strings that could take alphanumeric values and python allows different data structures like list, Tuple, Dictionary & sets for working with different problems.The Python ValueError: could not convert string to float occurs when you pass a string that can’t be converted into a float to the float() function. To resolve this error, you need to remove all elements that are non-compatible with float type like special characters and letters from the string.Oct 23, 2020 · Add a comment. 1. First use this line to obtain the current dtypes: col_dtypes = dict ( [ (k, v.name) for k, v in dict (df.dtypes).items ()]) Like so: xls3 = pd.read_csv ('path/to/file') col_dtypes = dict ( [ (k, v.name) for k, v in dict (xls3.dtypes).items ()]) print (col_dtypes) Copy the value that is printed. It should be like this: Aug 3, 2021 · You input a value (or more) and it predicts another. A float is a number with decimals. For example, a 2 is an integer and a 2.53 is a float. What you can do is. a = '0.67687980' print (float (a)) Which returns. 0.67687980. However, you cannot do it with a string. a = 'Some string' print (float (a)) May 8, 2022 · If you want to improve your model it is even recommended to normalize your model between -1;1 in general and therefore to use decimal numbers, hence the expectation of a float. In your case, your dataframe seems to contain exclusively string entries. As Dilara Gokay said, you first need to transform your strings into floats and to do so, use ... May 26, 2014 · 1. I'm trying to build a simple program using tkinter and I want to assign the value that the user enters into an entry widget as a float variable, not a string. Here is my code: from tkinter import * root = Tk () x_entry = Entry (root) x_entry.pack () x_string=x_entry.get () def enter_click (event): x=float (x_string) print (x) enter_button ... f1 = float ( "123.123" ) # output: 123.123 f2 = float ( "1" ) # output: 1.0 f3 = float ( 1 ) # output: 1.0. As you can see the above strings were converted into a floating object. The only thing you should keep in mind is that the string should contain a numerical decimal or integer value, only then would the float function be able to convert ... Sep 1, 2012 · This code works fine in python 2, but the input function was changed between python 2 and python 3 in compliance with PEP 3111:. What was raw_input in python 2 is now called just input in python 3. Hi I'm running this code to pick up data from a serial port and convert them into values. The data are in this form: b'-1.379531 -0.050295 ' The lines that I use to convert them into float. def separa_dati (text): try: return float (text) except ValueError: return text if z1serial.is_open: k = 0 while k <100: size = z1serial.inWaiting () if ...ValueError: could not convert string to float: id I'm confused by this. When I try this for only one line in interactive section, instead of for loop using script:– Replace the Unwanted Characters Using a Python Function. You can replace unwanted characters from your string using the “replace()” function. This will work for our previous pandas example, and the following string in our first example: “22,2.329%”.What this does is splits every item at the '-', and takes the first part and converts it to float. Items like this '9.8-10.0 ' cannot directly be converted to a float as they consist of a - in them. So you need to decide whether you want the first part (before -) to be converted to float or the second part (after the -).Though not the best solution, I found some success by converting it into pandas dataframe and working along. code snippet # convert X into dataframe X_pd = pd.DataFrame(data=X) # replace all instances of URC with 0 X_replace = X_pd.replace(' ',0, regex=True) # convert it back to numpy array X_np = X_replace.values # set the object type as float ... In Python, if you convert a string object into a floating point, you may face the ValueError could not convert the string to float numerous times. Usually, this happens if the string object is an invalid parameter to the float (). Code # decimal to float decimal_num = "10a" # invalid value float_num = float (decimal_num) float_num OutputValueError: could not convert string to float: 'Null' # else, only a single dtype is given # _astype_nansafe works fine with 1-d only # TODO(extension) # Explicit copy, or required since NumPy can't view from / to object. A try/except handles the ValueError that might occur when float tries to convert the input to a float. The problem is exactly what the Traceback log says: Could not convert string to float. If you have a string with only numbers, python's smart enough to do what you're trying and converts the string to a float.Maybe I should use other module to read CSV. I tried pandas right now, and it reads just fine as anyone would have expected, but OTOH I don't want to load huge package just to read CSV to array, and don't use it again...May 25, 2023 · Now, if you enter a string, this is how the output would look: Enter a number (precision up to at least one decimal place)= Hello Please enter a number as per instruction! And, if we give a proper float input, the output would be: Enter a number (precision upto atleast one decimal place)= 16.663 After dividing by 10 we get= 1.6663000000000001. Sep 7, 2017 · 3 Answers. A quick solution would involve using pd.to_numeric to convert whatever strings your data might contain to numeric values. If they're incompatible with conversion, they'll be reduced to NaN s. from sklearn.linear_model import LinearRegression X = X.apply (pd.to_numeric, errors='coerce') Y = Y.apply (pd.to_numeric, errors='coerce ... To convert string to float in Python, you can use the “float()” function. Pass the string you want to convert as an argument to the float() function, and it will return the float value. SyntaxMay 14, 2013 · 6. float (line) does not convert in-place. It returns the float value. You need to assign it back to a float variable. float_line = float (line) UPDATE: Actually a better way is to first check if the input is a digit or not. In case it is not a digit float (line) would crash. So this is better -. If your replacements result in with something that doesn't parse as float then astype will fail. You can use the pandas.to_numeric to handle problematic data using the "errors='coerce'" argument; the empty ('') values will be converted to NaN.Convert String to Float in Python. Below are 6 common and simple methods used to convert a string to float in python. 1) Using float() function. You can use the float() function to convert any data type into a floating-point number. This method only accepts one parameter. If you do not pass any argument, then the method returns 0.0.Matplotlib fails with ValueError: cannot convert float NaN to integer 0 TypeError: Image data of dtype object cannot be converted to float - Issue with HeatMap Plot using SeabornSep 1, 2012 · This code works fine in python 2, but the input function was changed between python 2 and python 3 in compliance with PEP 3111:. What was raw_input in python 2 is now called just input in python 3. Jul 21, 2019 · 5,534 3 25 36. asked Jul 21, 2019 at 14:51. Sudhanshu Kumar Tiwari. 1 1. 1. Somehow you are trying to convert the string 'f' to a float.It is probably in the .csv file. You'll have to find it and figure out why. – wwii. Jul 16, 2020 · Pythonは、コードの読みやすさが特徴的なプログラミング言語の1つです。 強い型付け、動的型付けに対応しており、後方互換性がないバージョン2系とバージョン3系が使用されています。 A solution to your question might be splitting the strings to represent two floating point numbers and then multiply them together, like in the following snippet: from sys import stderr callback = lambda x: stderr.write ('Invalid floating point number found: {0}'.format (x)) def convert (src, error_callback): ret = list () for item in src ...Jun 22, 2020 · If you're reading a CSV file with any data, I highly recommend to use Pandas.This would help you to use the data with Neural Networks as well. (Install Pandas)Below snippet will load the CSV into Pandas 2-dimensional data type called DataFrame. Aug 3, 2022 · This tutorial was tested with Python 3.9.6. Using the float() function. We can convert a string to float in Python using the float() function. This is a built-in function used to convert an object to a floating point number. Internally, the float() function calls specified object __float__() function. Example Matplotlib fails with ValueError: cannot convert float NaN to integer 0 TypeError: Image data of dtype object cannot be converted to float - Issue with HeatMap Plot using SeabornThe problem is that your string is not just '1151226468812.22', but it is '"1151226468812.22"'. It also contains speech marks ( " ). This means that before you convert this to a float, you need to remove the leading and trailing speech marks. Luckily, Python has a very handy string method .strip () to do this for you.Apr 28, 2023 · The Python ValueError: could not convert string to float occurs when you pass a string that can’t be converted into a float to the float() function. To resolve this error, you need to remove all elements that are non-compatible with float type like special characters and letters from the string. ValueError: could not convert string to float: 'X_train' ... not able to convert string to float in python and how to train the model with this dataset. 5.In: merged['platnosc_total'].astype(float) Out: ValueError: could not convert string to float: '7,50' Does this mean that the rest got converted, and only the row with 7,50 is the cause? How can I actually cast this field/column to float?How to fix these errors . There are 4 methods to fix this issue. Those are: Remove all characters, and symbols, and extract only the number (using re) Remove leading and trailing unwanted characters (using `str.strip`) Replace the unnecessary character (s) with an empty string (using `str.replace`) Using try-catch logic.Sep 30, 2015 · Hi @adityashrm21,. In that case I assume that you are able to run your random forest. So I don’t know how to do this by using function, but it can be done by following steps -
Aug 16, 2022 · To convert string to float we can use the function: .astype(float). If we try to do so for the column - amount: df['amount'].astype(float) we will face error: ValueError: could not convert string to float: '$10.00' Step 2: ValueError: Unable to parse string "$10.00" at position 0. We will see similar result if we try to convert the column to ... . Oh i think you
In: merged['platnosc_total'].astype(float) Out: ValueError: could not convert string to float: '7,50' Does this mean that the rest got converted, and only the row with 7,50 is the cause? How can I actually cast this field/column to float?Maybe I should use other module to read CSV. I tried pandas right now, and it reads just fine as anyone would have expected, but OTOH I don't want to load huge package just to read CSV to array, and don't use it again... Like the comments said, you are trying to convert a string or object (in this case "Male") into a float. Try to output your variables and their types to makes you see where you are trying to convert the float.May 8, 2022 · If you want to improve your model it is even recommended to normalize your model between -1;1 in general and therefore to use decimal numbers, hence the expectation of a float. In your case, your dataframe seems to contain exclusively string entries. As Dilara Gokay said, you first need to transform your strings into floats and to do so, use ... Sep 7, 2017 · 3 Answers. A quick solution would involve using pd.to_numeric to convert whatever strings your data might contain to numeric values. If they're incompatible with conversion, they'll be reduced to NaN s. from sklearn.linear_model import LinearRegression X = X.apply (pd.to_numeric, errors='coerce') Y = Y.apply (pd.to_numeric, errors='coerce ... float('fd') # Traceback (most recent call last): # File "example.py", line 11, in <module> # ValueError: could not convert string to float: 'fd' How to Solve ValueError: could not convert string to float. In order to solve it, you can use the try...except block.ValueError: could not convert string to float: '$257.26' - sklearn.tree.DecisionTreeClassifier - Python Hot Network Questions Galois action on automorphisms of a curveI'm trying to load the two coluns of my csv files into an array in python. However I am getting: ValueError: could not convert string to float: ''. I have attached the snippets of the code implemented and the csv file I'm trying to store in an array.Mar 31, 2020 · Like the comments said, you are trying to convert a string or object (in this case "Male") into a float. Try to output your variables and their types to makes you see where you are trying to convert the float. Apr 25, 2015 · A solution to your question might be splitting the strings to represent two floating point numbers and then multiply them together, like in the following snippet: from sys import stderr callback = lambda x: stderr.write ('Invalid floating point number found: {0}'.format (x)) def convert (src, error_callback): ret = list () for item in src ... Jan 6, 2022 · with open ("n38bn.txt", r, encoding="utf-8") as file: # Open the file for the length of the width block numbers = [float (line.strip ()) for line in file] # For each line, strip, convert to float and add to list result = sum (numbers) # Sum the list print ("The sum is", result) This uses a list comprehension to build the list in one line, and ... Read the input strvalue and use float () to convert it to a float type. Args: strvalue (str): The input string. Returns: True if strvalue is a string that can be converted to a float type, otherwise False. """ try: myfloat = float (strvalue) except ValueError: print (f'The input string {strvalue} cannot be converted to a float type.') else ...f1 = float ( "123.123" ) # output: 123.123 f2 = float ( "1" ) # output: 1.0 f3 = float ( 1 ) # output: 1.0. As you can see the above strings were converted into a floating object. The only thing you should keep in mind is that the string should contain a numerical decimal or integer value, only then would the float function be able to convert ...Jun 9, 2015 · I think np.loadtxt expects numbers so it does not know how to convert a value which starts with a ' (', I think you have two choices here: lines = [] with open ('datafile') as infile: for line in infile: line = line.rstrip (' ') [1:-1] # this removes first and last parentheses from the line lines.append ( [float (v) for v in line.split ... – Replace the Unwanted Characters Using a Python Function. You can replace unwanted characters from your string using the “replace()” function. This will work for our previous pandas example, and the following string in our first example: “22,2.329%”. Hi @adityashrm21,. In that case I assume that you are able to run your random forest. So I don’t know how to do this by using function, but it can be done by following steps -could not convert string to float: and not the Exception that i wrote it. raise Exception("this Record has empty value") row[0]==> Date type Date; row[10]==> wind speed type float; row[11]==> fog type boolean; code:It is most likely a problem with the data. Since you don't have any point in the code where you attempt to convert to float, it must be that the data you have is in a form that prevents it from being read as a number by your parsing commands.Dec 27, 2020 · Convert string to float object in python in python. Suppose we have a string ‘181.23’ as a Str object. To convert this to a floating-point number, i.e., float object, we will pass the string to the float() function. Which converts this string to a float and returns the float object. For example, Sep 1, 2012 · This code works fine in python 2, but the input function was changed between python 2 and python 3 in compliance with PEP 3111:. What was raw_input in python 2 is now called just input in python 3. .