Straight-Line Source Code

In straight-line source code withoutif,while,fororswitchstatements, the comment containing the source code precedes the generated code that implements the source code statement. This comment appears after user comments that precede the generated code.

For example, in the following code, the user comment,/ *Convert polar to Cartesian */, appears before the generated comment containing the first line of source code, together with its traceability tag,
/ *'straightline:4' x = r * cos(theta); */.

MATLAB Code

function[x, y] = straightline(r,theta)%#codegen% Convert polar to Cartesianx = r * cos(theta); y = r * sin(theta);

Commented C Code

void straightline(double r, double theta, double *x, double *y) { /* Convert polar to Cartesian */ /* 'straightline:4' x = r * cos(theta); */ *x = r * cos(theta); /* 'straightline:5' y = r * sin(theta); */ *y = r * sin(theta); }

If Statements

The comment for theifstatement immediately precedes the code that implements the statement. This comment appears after user comments that precede the generated code. The comments for theelseifandelseclauses appear immediately after the code that implements the clause, and before the code generated for statements in the clause.

MATLAB Code

functiony = ifstmt(u,v)%#codegenifu > v y = v + 10;elseifu == v y = u * 2;elsey = v - 10;end

Commented C Code

double ifstmt(double u, double v) { double y; /* 'ifstmt:3' if u > v */ if (u > v) { /* 'ifstmt:4' y = v + 10; */ y = v + 10.0; } else if (u == v) { /* 'ifstmt:5' elseif u == v */ /* 'ifstmt:6' y = u * 2; */ y = u * 2.0; } else { /* 'ifstmt:7' else */ /* 'ifstmt:8' y = v - 10; */ y = v - 10.0; } return y; }

For Statements

The comment for theforstatement header immediately precedes the generated code that implements the header. This comment appears after user comments that precede the generated code.

MATLAB Code

functiony = forstmt(u)%#codegeny = 0;fori = 1:u y = y + 1;end

Commented C Code

double forstmt(double u) { double y; int i; /* 'forstmt:3' y = 0; */ y = 0.0; /* 'forstmt:4' for i = 1:u */ for (i = 0; i < (int)u; i++) { /* 'forstmt:5' y = y + 1; */ y++; } return y; }

While Statements

The comment for thewhilestatement header immediately precedes the generated code that implements the statement header. This comment appears after user comments that precede the generated code.

MATLAB Code

functiony = subfcn(y) coder.inline('never');whiley < 100 y = y + 1;end

Commented C Code

void subfcn(double *y) { /* 'subfcn:2' coder.inline('never'); */ /* 'subfcn:3' while y < 100 */ while (*y < 100.0) { /* 'subfcn:4' y = y + 1; */ (*y)++; } }

Switch Statements

The comment for theswitchstatement header immediately precedes the generated code that implements the statement header. This comment appears after user comments that precede the generated code. The comments for thecaseandotherwiseclauses appear immediately after the generated code that implements the clause, and before the code generated for statements in the clause.

MATLAB Code

functiony = switchstmt(u)%#codegeny = 0;switchucase1 y = y + 1;case3 y = y + 2;otherwisey = y - 1;end

Commented C Code

double switchstmt(double u) { double y; /* 'switchstmt:3' y = 0; */ /* 'switchstmt:4' switch u */ switch ((int)u) { case 1: /* 'switchstmt:5' case 1 */ /* 'switchstmt:6' y = y + 1; */ y = 1.0; break; case 3: /* 'switchstmt:7' case 3 */ /* 'switchstmt:8' y = y + 2; */ y = 2.0; break; default: /* 'switchstmt:9' otherwise */ /* 'switchstmt:10' y = y - 1; */ y = -1.0; break; } return y; }