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+--- Thread: Upload csv file as numbers (floating?) and extract element, row, and column (/thread-9000.html)
Upload csv file as numbers (floating?) and extract element, row, and column - bentaz - Mar-16-2018
Hello,
I've been trying for a couple days to upload a csv file as a 2D matrix of numerical values (e.g. 1+2=3) so that I can extract individual numbers, rows, and, columns. I am using numpy. The input csv file is has four rows and three columns.
This is as close as I've gotten:
import numpy as np
import csv
with open('C:\\Users\\...\\matrix.csv') as File:
reader = csv.reader(File, delimiter=',')
for data in reader:
data = np.matrix(data, dtype=float)
x = data.shape
print (x)This gives me four 1x3 matrices instead of a 4x3 matrix. Thoughts?Thank you,
Ben
RE: Upload csv file as numbers (floating?) and extract element, row, and column - Larz60+ - Mar-16-2018
I modified you code, and removed absolute link.
Could you please give a sample of matrix.csv (enough for a complete entry)
RE: Upload csv file as numbers (floating?) and extract element, row, and column - bentaz - Mar-16-2018
Hi Larz,
The matrix.csv is just:
1 5 9
2 6 10
3 7 11
4 8 12
Is there any way to upload files here?
Thanks
RE: Upload csv file as numbers (floating?) and extract element, row, and column - Larz60+ - Mar-16-2018
That's not a CSV (Comma Separated Values) file!
There are no comma's!
RE: Upload csv file as numbers (floating?) and extract element, row, and column - bentaz - Mar-16-2018
That is an excellent point! That's why I asked about uploading files.
That matrix (or 2D array if you prefer) is saved in a .csv spreadsheet and then uploaded into Python.
I.e. copy and paste those numbers into an excel file and save as a .csv file.
I used this instead:
import pandas as pd import numpy as np filename = 'C:\\Users\\bpt6\\Desktop\\OxideThicknessTest2\\matrix2.csv' data = pd.read_csv(filename, header = None); data = data.values ; ###Convert DataFrame to array of values (numbers) data = data.astype(np.float); ###Convert for scientific notation to floatingThanks anyway.
RE: Upload csv file as numbers (floating?) and extract element, row, and column - DeaD_EyE - Mar-16-2018
Uploaded is the wrong description what you want to do.
You're opening a file and reading from a file. This has nothing to do with upload.
I guess you copied some snippets from some places and you don't know what you're doing.
If you want to split a space separated table, use the split method.
with open('your-file.text') as fd:
for line in fd:
rows = line.split()
print(rows)You should look into string-methods.
RE: Upload csv file as numbers (floating?) and extract element, row, and column - bentaz - Mar-16-2018
My apologies for using the word "upload" instead of "open and read" in the first post. Egg on my face for sure.
After that I WAS asking how to upload files (a .csv file) to this forum of kind souls. The space separated example matrix I posted was to show what I meant by the 4x3 matrix which I described in the post, since matrix means different things in different languages. I thought the commas were implied. More egg on my face.
You're right. I don't know what I'm doing in Python. If I did I wouldn't be asking what should be simple questions. I'm trying to convert programs from MATLAB. I guess MATLAB made me soft since all it requires is:
X = importdata('C:\Desktop\matrix.csv');
Where's the fun in that, right?
Thanks for your help,
Ben
RE: Upload csv file as numbers (floating?) and extract element, row, and column - bentaz - Mar-19-2018
I think I did a better job of posting on my next question:
https://python-forum.io/Thread-Convert-indexing-For-Loop-from-MATLAB-uses-numpy-and-pandas
if you want to give it a shot.