HELP PLEASE!! How do I print matlab "1:5 multiply increases each line"

This is my code

clc
fprintf ('     SGD       USD       GBP       EURO \n')
for (x= 1 : 5)
    USD = 0.69 *2;
    GBP = 0.49 *2;
    EURO = 0.64 *2;
    fprintf (' \n      %d        %.2f      %.2f      %.2f ' ,SGD ,USD ,GBP ,EURO);
end

My results

     SGD       USD       GBP       EURO 

      1        1.38      0.98      1.28  
      1        1.38      0.98      1.28  
      1        1.38      0.98      1.28  
      1        1.38      0.98      1.28  
      1        1.38      0.98      1.28 >>

I want the 2nd line to multiple by two, the thrid line to multiple by three... so on and so fourth...

Answer 1

[Stephen23]

Without any loops, using vectorized code. Note that you can simply add new currencies to the arrays and it will work perfectly (i.e. changing the code itself is not required):

% the arrays:
name = {'SGD','USD','GBP','EURO'};
xchg = [    1, 0.69, 0.49,  0.64];
mult = [1:5,10,20]; % multiples
% the code:
fprintf('%8s',name{:})
fprintf('\n')
fmt = repmat('%8.2f',1,numel(name));
fprintf([fmt,'\n'],xchg(:)*mult)

prints this:

     SGD     USD     GBP    EURO
    1.00    0.69    0.49    0.64
    2.00    1.38    0.98    1.28
    3.00    2.07    1.47    1.92
    4.00    2.76    1.96    2.56
    5.00    3.45    2.45    3.20
   10.00    6.90    4.90    6.40
   20.00   13.80    9.80   12.80

[Ken kaneki]

Oh god... It took me hours to do it and yet you completed it in few sec... I guess i need to work harder... Is there any simply way to do it? I don't understand some of the parts.... But still thanks for your answer!

[Stephen23]

My pleasure. Here are a few tips to understand how my solution works:

1. fprintf keeps repeating its format until it runs out of values to work with: this means that fprintf('%f,',1:3) prints '1,2,3,'.
2. The minimum total width of the output can be set: fprintf('%4f',1) prints '___1' (three spaces are indicated here by three underscores).
3. The product xchg(:)*mult calculates all values at once in a matrix. Try it in your command window!

Now you should be able to understand how it works. Of course the fprintf documentation explains how it behaves, that is where I learned how to do these kind of things.

[Ken kaneki]

Thanks Stephen, i'm slowly digesting it hahaha! I guess it's gonna take awhile...

Answer 2

[C.J. Harris]

Do you mean like this?

clc 
fprintf(' SGD USD GBP EURO \n') 
for x= 1 : 5 
    USD = 0.69 * 2 * x; 
    GBP = 0.49 * 2 * x;
    EURO = 0.64 * 2 * x;
    SGD = x;
    fprintf (' \n %d %.2f %.2f %.2f ' ,SGD ,USD ,GBP ,EURO); 
end

Result:

   SGD USD GBP EURO 

   1 1.38 0.98 1.28  
   2 2.76 1.96 2.56  
   3 4.14 2.94 3.84  
   4 5.52 3.92 5.12  
   5 6.90 4.90 6.40

[Ken kaneki]

Thank you guys for your time and offered help to me, really really appreciated. The mistake i made was I didn't add the * x; !!