How to find and chart the frequency of a letter in column with histogram.

I am looking for a way to find the frequency of a letter appearing in each line of a column in an excel file. The only column I am looking at has data like this: HFHFHSHHAJHJA, HSAJHFGFSAGJ, HSGHSFFJHJ. All I have found online so far, specifically through the mathworks resources is

T = readtable('Data.xlsx');
Sets = T{:, 9};
histogram(Sets, 40, 'FaceAlpha',0.4);

Basically I am trying to find the frequency H appears in each line and then the total frequency of the column.

Thank you for your help.

Answer 1

[Star Strider]

Perhaps —

Col = {'HFHFHSHHAJHJA'; 'HSAJHFGFSAGJ'; 'HSGHSFFJHJ'};
T = cell2table(Col)

T = 3×1 table
           Col       
    _________________

    {'HFHFHSHHAJHJA'}
    {'HSAJHFGFSAGJ' }
    {'HSGHSFFJHJ'   }

RowSum = cellfun(@(x)sum(x=='H',2),T{:,1})

RowSum = 3×1

6 2 3

ColSum = sum(RowSum)

ColSum = 11

.

[rogox]

Thank you for this, it is a good start, but how would I make use of a histogram stating the frequency of the H in each line for example the first one being 46%.

[Star Strider]

I was not certain how you were going to implement a histogram with that, since it is not obvious what you want to count (other than the letter ‘H’), and none of the histogram functions work with letters (either character arrays or string variables).

If you want the proportion of ‘H’ in each row:

Col = {'HFHFHSHHAJHJA'; 'HSAJHFGFSAGJ'; 'HSGHSFFJHJ'};
T = cell2table(Col)

T = 3×1 table
           Col       
    _________________

    {'HFHFHSHHAJHJA'}
    {'HSAJHFGFSAGJ' }
    {'HSGHSFFJHJ'   }

RowSum = cellfun(@(x)sum(x=='H',2),T{:,1})

RowSum = 3×1

6 2 3

ColSum = sum(RowSum)

ColSum = 11

LetterCount = cellfun(@numel, T{:,1})

LetterCount = 3×1

13 12 10

H_Pct_Row = 100 * RowSum ./ LetterCount

H_Pct_Row = 3×1

46.1538 16.6667 30.0000

.

[rogox]

So basically it would be a histogram showing the percentage of H in the data set. Sorry for not being clear enough.

[Star Strider]

In that event, just use bar with ‘H_Pct_Row’.