CODEWITHSUNDEEP
pythoninputmatplotlib
sbowde4
sbowde4

Reputation: 777

TypeError: Float() argument must be a string or a number when reading a list()

I am currently working on a simple demo that reads an excel file with two columns and extracts the data from each row of the columns into two different lists.

That all works fine, but when I try to plot the data using matplotlib I get this error.

TypeError: float() argument must be a string or a number

I understand that the error is being caused by the float values in the second list, the should just be integers. What I do not understand is how to prevent them from becoming floats when they are read into the list. 

[text:u'Joe', text:u'Sam', text:u'Bobby', text:u'Tom', text:u'Jane']
[number:23.0, number:36.0, number:19.0, number:31.0, number:28.0]

I have tried typecasting in several different places, but always get the same error.

TypeError: int() argument must be a string or a number, not 'Cell'

Here is the method that I am using for this program

def bargraph(self, fileName, xlabel, title):
        people = list()
        dollars = list()
        workbook = xlrd.open_workbook(fileName)
        worksheet = workbook.sheet_by_index(0)

        for row in range(worksheet.nrows):
            people.append(worksheet.cell(row ,0))

        for row in range(worksheet.nrows):
            dollars.append(worksheet.cell(row, 1))


        plt.bar(people, dollars, 1, color="blue")
        plt.xlabel(xlabel) 
        plt.title(title)
        plt.show()

Upvotes: 1

Views: 1689

Answers (1)

Elwin Arens
Elwin Arens

Reputation: 1602

This error occurs because with worksheet.cell(row, idx) you retrieve a Cell instance. So you're creating a list of Cells, while the plotting library requires a list of ints.

Try looking at using the functions worksheet.cell_value and worksheet.cell_type of the xlrd library. For example try:

for row in range(worksheet.nrows):      
    people.append(worksheet.cell_value(row ,0))

for row in range(worksheet.nrows):
    dollars.append(worksheet.cell_value(row, 1))

Upvotes: 1

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