topic Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric in SAS/IML Software and Matrix Computations

NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

desireatem — Wed, 24 Sep 2014 13:45:30 GMT

Please, I wish to ask if any could help correct this error:

NOTE: Module FUNC defined.

47 interval = {A, B};

48 call quad(answer, "Func", interval);

param must be numeric

ERROR: (execution) Character argument should be numeric

This is data set and code:

Data sim;

Input A B;

cards;

1 3

2 7

3 10

4 12

;

Run;

proc iml;

use sim;

read all var{A B} into DM;

close;

A = DM[,1]; B = DM[,2];

n = nrow(DM);

start Func(x);

return( exp(2-x)#cdf("Normal", x) );

finish;

interval = {A, B};

call quad(answer, "Func", interval);

create kaplan1n var{A B Answer };

append;

quit;

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

Rick_SAS — Wed, 24 Sep 2014 14:30:20 GMT

If you are trying to compute four integrals, use the i_th row of DM as the interval for the i_th computation:

do i = 1 to nrow(DM);

call quad(answer, func, DM[i,]);

...

end;

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

desireatem — Wed, 24 Sep 2014 18:35:08 GMT

Hello Rick, My interval is A, B. The lower limit is A and upper limit is B, , the code does not specified the upper and lower limit. I have to pick the correct limit .

do i = 1 to nrow(DM);

call quad(answer, func, DM[i,]);

...

end;

I modified my code as such:

Data sim;

Input A B;

cards;

1 3

2 7

3 10

4 12

;

Run;

proc iml;

use sim;

read all var{A B} into DM;

close;

A = DM[,1]; B = DM[,2];

n = nrow(DM);

start Func(x);

return( exp(2-x)#cdf("Normal", x) );

finish;

do i = 1 to nrow(DM);

call quad(answer, "Func", DM[i,]);

end;

create kaplan1n var{A B Answer };

append;

quit;

statement : CALL at line 8281 column 1

ERROR: (execution) Matrices do not conform to the operation.

operation : QUAD at line 8307 column 1

operands : *LIT1007, _TEM1001

*LIT1007 1 row 1 col (character, size 4)

Func

_TEM1001 1 row 1 col (numeric)

statement : CALL at line 8307 column 1

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

Rick_SAS — Wed, 24 Sep 2014 18:44:04 GMT

Your error is that DM[1,2] is a scalar, whereas QUAD is expecting a vector with two elements, as in my code. You could also use A || B, if you prefer.

Of course, you also will want to accumulate the results inside the loop. Currently you are just overwriting ANSWER four times, and the data set is only writing the answer to the last integration.

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

desireatem — Wed, 24 Sep 2014 18:57:53 GMT

Thanks a lot. Yes you are right,

This just give me one answer and I need a result for each row.

This code below gives me and answer. How ever, just as you said , it is not giving me the answer for each row. How do I loop it from 1 to 4 so that each row has an answer. ?

Data sim;

Input A B;

cards;

1 3

2 7

3 10

4 12

;

Run;

proc iml;

use sim;

read all var{A B} into DM;

close;

A = DM[,1]; B = DM[,2];

n = nrow(DM);

start Func(x);

return( exp(2-x)#cdf("Normal", x) );

finish;

do i = 1 to nrow(DM);

call quad(answer, "Func", A || B,);

end;

create kaplan1n var{A B Answer };

append;

quit;

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

Rick_SAS — Wed, 24 Sep 2014 19:11:06 GMT

You want to allocate a vector outside of the loop and fill it within the loop, as described in this article: Pre-allocate arrays to improve efficiency - The DO Loop

This and other efficiency tips that you've asked about are found in Chapter 2 of Statistical Programming with SAS/IML Software

answer = j(nrow(A),1);

do i = 1 to nrow(A);

call quad(result, "Func", A||B);

answer = result;

end;

Re: NUMERICAL INTEGRATION: ERROR: (execution) Character argument should be numeric

desireatem — Wed, 24 Sep 2014 19:23:18 GMT

Data sim;

Input A B;

cards;

1 3

2 7

3 10

4 12

;

Run;

proc iml;

use sim;

read all var{A B} into DM;

close;

A = DM[,1]; B = DM[,2];

n = nrow(DM);

start Func(x);

return( exp(2-x)#cdf("Normal", x) );

finish;

answer = j(nrow(DM),1);

do i = 1 to nrow(DM);

call quad(result, "Func", A || B,);

answer = result;

end;

create kaplan1n var{A B Answer };

append;

quit;