Replace NaN with Blanks

Hi guys I have a double matrix as shown in the attached picture that I am trying to replace all NaN values with Empty spaces so that the over all matrix dimension will be maintained. However, when I looked through the function and suggested solutions non of them is actully working what possible code can be used.

Thanks in advance

Answer 1

[Walter Roberson]

It is not possible to have a numeric array that has blanks in it.

You can use

fillmissing(V1, 'constant', 0)

to replace the NaN entries with 0... or you could do

V1(isnan(V1)) = 0;

for the same effect.

If you need a blank then you will need to convert to cell array, such as

V1c = num2cell(V1);
mask = cellfun(@(C) all(isnan(C)), V1c);
V1c(mask) = {' '};

If you do this, then the variable browser will show ' ' (including the quotes) in those locations but the quote marks are not part of the content. disp(V1c) would show ugly things like

    {[  1]}    {[  1]}    {[  1]}    {[2]}    {[3]}
    {'   '}    {[  3]}    {[  2]}    {[1]}    {[3]}
    {[  2]}    {'   '}    {[  3]}    {[3]}    {[2]}
    {[  3]}    {[  2]}    {[  3]}    {[3]}    {[2]}
    {[  3]}    {[  3]}    {'   '}    {[3]}    {[1]}

[Abdullah Azzam]

What I am trying to do is combining 2 array one contain string and the other contains the value. But when I try to do that the NaN or empty space overwrite the other spaces.

Assuming the same example above but some of the NaNs has string on them in another array with same dimension. Is there away to combine these 2 array as one.

[Walter Roberson]

You can use a cell array, or you can use a table, or you can use a struct.

However, it is impossible in MATLAB to have a numeric array that contains (for example)

-10 7 trace
-4 -2 none
 3  9 5 mm

Numeric arrays cannot contain characters. Non-numeric arrays such as cell arrays do not display anything like the above example by default -- to display like that you would have to write a small bit of code to do the formatting into characters.

[Abdullah Azzam]

Ok. Then how may I import an excel sheet that contain both numaric and string value into the matlab. Note if it isn't possible I don't mind if the numric were saved as strings

[Walter Roberson]

readtable() is what is recommended these days.

Or you could xlsread() . The first input will contain only numeric parts, the second output will contain text without numbers, and the third will contain both. But readtable() is typically better.

In some cases it might be more suitable to use readcell() for R2019b and later.

Answer 2

[dpb]

Can't be done--a double array has to be regular in both dimension; can't have holes.

Only possibility is to convert to a cell array.

Answer 3

[Opeyemi Kehinde]

fillmissing(V1, 'constant', [])

will this work to make NaN an empty entry

[Walter Roberson]

@Opeyemi Kehinde

Let us test:

V1 = [1 2 nan 3; 4 nan 5 6]

V1 = 2×4

1 2 NaN 3 4 NaN 5 6

fillmissing(V1, 'constant', [])

Error using fillmissing/checkConstantsSize (line 740)
Fill constant must be a scalar or a 4-element vector.

Error in fillmissing/parseInputs (line 680)
intConstOrWindowSize = checkConstantsSize(A,AisTable,false,intConstOrWindowSize,dim,dataVars,'');

Error in fillmissing (line 158)
[A,AisTable,intM,intConstOrWinSize,extM,x,dim,dataVars,ma,maxgap] = parseInputs(A,fillMethod,varargin{:});

So... NO.

[Opeyemi Kehinde]

Thank you!