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The array AxisArray can't contain two same parallel loop dimension numbers.

The sizes of AxisArray, CoeffArray and ConstArray arrays must be equal to remote distributed array rank.

Correct sampling rules must not violate remote distributed array boundaries.

The base pointer BasePtr must refer to any variable of the same type as the type of the remote distributed array elements. The variable value is irrelevant, because the base pointer is used only for access to remote elements of the distributed array, allocated in the created buffer.

Dealing with the header of remote elements buffer and base pointer is considered in detail in section Error: Reference source not found.

If the flag *StaticSignPtr of static buffer is not equal to zero, then the created buffer will be not deleted automatically, when the control exits the program block (see section Error: Reference source not found). Such buffer can be deleted only explicitly using the function delrb_ considered below.

The function returns non-zero, if created buffer has a local part on the current processor, and zero in other case.

Note 1. If all sampling rules are constant ones, created buffer rank must be zero by virtue of writing above. In this case Run-Time System creates one-dimensional distributed array-buffer, containing single element.

Note 2. Let when parallel loop is mapped by mappl_ function for some dimension initial value of index variable is more than its last value for positive step or its last value of index variable is more than its initial value for negative step (empty loop). Then these loop usage as crtrbl_ function parameter will be resulted in creation of dummy remote element buffer. 0-th word of the buffer header (distributed array reference) will be assigned by null value. Dummy remote element buffer can be used in all remote access functions, but it is not allowed to use the buffer header as parameter of the functions, dealing with distributed arrays. An access to local part of distributed array by dummy buffer header is not allowed also.

The buffer of remote elements, required for parallel loop and for program branches, that are not the loop iterations, can be also created by crtrba_ and crtrbp_ functions considered below.

The function crtrba_ creates the buffer to locate remote elements of distributed array with RemArrayHeader header, which are required to deal with distributed (local) array, specified by LocArrayHeader. Remote and local distributed arrays must be mapped on the processor systems (perhaps, each one in its own), all elements of which belong to the current processor system.

Required elements of remote distributed array are specified for each its not-free dimension by linear sampling rules as:

A_i*V_k(i) + B_i , where:

The remote element buffer, created by crtrba_ function is mapped just as the local distributed array, but its i-th dimension is matched with k(i)-th dimension of the local array (in the case, when linear sampling rule with non-zero A_i is specified for i-th dimension of the remote array).

All parameters of crtrba_ function (except LocArrayHeader) are similar to same named parameters of crtrbl_ function, considered above.

The function returns non-zero, if created buffer has a local part on the current processor, and zero in other case.

The function crtrbp_ creates the buffer to locate remote elements of distributed array with RemArrayHeader header, which must be present on each processor of the system, specified by *PSRefPtr reference.

Remote distributed array must be mapped on the processor system, all elements of which must belong to the current processor system. *PSRefPtr reference defines the current processor system or its direct or indirect subsystem. NULL value of PSRefPtr pointer or zero value of *PSRefPtr reference specify the current processor system.

Required elements of remote distributed array for (i+1)-th dimension are defined by i-th word of CoordArray array: non-negative value defines remote array element coordinate, negative one specifies whole dimension of the remote array (analogue of free dimension of the remote array in crtrbl_ and crtrba_ function description). A number of elements in CoordArray array must be equal to remote distributed array rank.

The rank of remote element buffer, created by crtrbp_ function, is equal to a number of negative elements of CoordArray array. The size of j-th buffer dimension is equal to j-th negative element of CoordArray array. If all elements of CoordArray array are non-negative (exactly one remote element is specified), Run-Time System creates one-dimensional distributed array-buffer, consisting of single element.

While executing crtrbp_ function, remote element buffer is mapped so that all required, and therefore, located in the buffer remote elements assist on all processors of the system, specified by PSRefPtr parameter. To do this, Run-Time System creates subsidiary one-dimensional representation of the current abstract machine, consisting of single element and maps it with replication on all dimensions on specified in the function call processor system. Remote element buffer is mapped on subsidiary representation with replication on its single dimension.

The function returns non-zero, if created buffer has a local part on the current processor, and zero in other case.

14.2Initializing loading remote element buffer of distributed array

The function loadrb_ initializes specified buffer loading by the distributed array elements, for which the buffer was created by crtrbl_, crtrba_ or crtrbp_ function.

The function can be used for already loaded buffer. In this case actual reloading is performed if *RenewSignPtr is not equal to zero, and isn't performed otherwise. The buffer reloading is not allowed (independently on *RenewSignPtr parameter value), if previous loading (actual or dummy) was not completed by waitrb_ function (see section 14.3).

As loaded buffer as its remote distributed array must be mapped on the processor systems, which each element must belong to the current processor system.

The buffer loading can't be started by loadrb_ function, if it was included in any buffer group (see sections 14.6-14.10).

The function returns zero.

14.3Waiting for completion of loading remote element buffer of distributed array

long waitrb_ (long BufferHeader[]);

BufferHeader  header of the remote element buffer.

Loading the buffer specified in the function call must be initialized by the current subtask. Waiting for completion of not initialized earlier buffer loading is not allowed.

The function returns zero.

14.4Deleting remote element buffer of distributed array

long delrb_ (long BufferHeader[]);

BufferHeader  header of the remote element buffer to be deleted.

The remote element buffer can be deleted by delrb_ function only if it was created in the current subtask and in the current program block (or its sub-block) (see sections 8 and 10).

To delete remote element buffer the function delobj_ can also be used (see section 17.5).

The buffer, which loading is not completed by waitrb_ function, can't be deleted.

If deleted buffer was included in any buffer group, it is excluded from the group (see sections 14.6-14.10). In this case the buffer group must not be in loading state.

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