1: $iw (leniw)$ – Integer array Communication Array
2: $leniw$ – Integer Input: On entry: the dimension of the array iw as declared in the (sub)program from which e04wcf is called.

Constraint: $leniw \geq 600$ , see routine e04wdf.
3: $rw (lenrw)$ – Real (Kind=nag_wp) array Communication Array
4: $lenrw$ – Integer Input: On entry: the dimension of the array rw as declared in the (sub)program from which e04wcf is called.

Constraint: $lenrw \geq 600$ , see routine e04wdf.
5: $ifail$ – Integer Input/Output: On entry: ifail must be set to $0$ , $−1$ or $1$ to set behaviour on detection of an error; these values have no effect when no error is detected.
A value of $0$ causes the printing of an error message and program execution will be halted; otherwise program execution continues. A value of $−1$ means that an error message is printed while a value of $1$ means that it is not.

If halting is not appropriate, the value $−1$ or $1$ is recommended. If message printing is undesirable, then the value $1$ is recommended. Otherwise, the value $0$ is recommended. When the value $- 1$ or $1$ is used it is essential to test the value of ifail on exit.

On exit: $ifail = 0$ unless the routine detects an error or a warning has been flagged (see Section 6).

6 Error Indicators and Warnings

If on entry

ifail = 0

−1

, explanatory error messages are output on the current error message unit (as defined by x04aaf).

Errors or warnings detected by the routine:

$ifail = 1$: On entry, $leniw = ⟨ value ⟩$ .
Constraint: $leniw \geq 600$ .

On entry, $lenrw = ⟨ value ⟩$ .
Constraint: $lenrw \geq 600$ .

$ifail = - 99$: An unexpected error has been triggered by this routine. Please contact NAG.
See Section 7 in the Introduction to the NAG Library FL Interface for further information.

$ifail = - 399$: Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library FL Interface for further information.