eliminating, whenever is necessary the first column in nun where [num,txt,r​aw]=xlsrea​d('data.xl​sx');

Dear all, I am struggling to find a solution to the following problem. I load many excel files Say for instance that I load the following file

[num,txt,raw]=xlsread('data.xlsx');

The problem is that sometimes the first column of the “raw” matix, which normally contains this type of information

[ NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    ' YEs'

    'NO'

Contains also numbers in some cells. For example

     [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    [          NaN]

    ' YEs'

    'NO'

    [            0]

 As a result of this situation, the matrix “num” , creates a first column which is useless as it contain no information(it contains only NaN and zeros). If the first column of the “raw” matrix contains no numbers then such useless column does not appear in “num”

My goal was to develop a code that could identify this problem and eliminate, whenever is needed, the first useless column from “num”

So far I have made no progress

thanks

[Sabbas]

I have an idea. The first column of “num” will be useless is it contains ONLY NaNs AND zeros

So I am looking for something like

if isnan(num(:,1)) & num(:,1) contains zeros

num(:,1)=[]

end

I have some difficulty, though , with the expression

if isnan(num(:,1)) & num(:,1) contains zeros

thanks

[Walter Roberson]

xlsread() will treat top-most rows or left-most columns as being headers if it thinks the columns are text.

Answer 1

[Kye Taylor]

I like your approach.

try

if all (isnan(num(:,1)) | num(:,1) == 0) 
  num(:,1) = [];
end

note that there may still be some NaNs in the first column. To remove the first column whenever any nan is present, try

if any(isnan(:,1))
  num(:,1) = [];
end

[Sabbas]

very good! thank you!