Title here
Summary here
Select in Scilab
Our example demonstrates how to wait on multiple channel-like operations. Combining parallel execution and communication channels is a powerful feature in scientific computing.
function select_example()
// For our example we'll select across two channels.
c1 = [];
c2 = [];
// Each channel will receive a value after some amount
// of time, to simulate e.g. blocking operations
// executing in parallel.
function delayed_send(channel, value, delay)
sleep(delay * 1000);
channel($+1) = value;
endfunction
parallel_run(delayed_send, list(c1, "one", 1));
parallel_run(delayed_send, list(c2, "two", 2));
// We'll use a loop to await both of these values
// simultaneously, printing each one as it arrives.
for i = 1:2
while isempty(c1) & isempty(c2)
sleep(100);
end
if ~isempty(c1) then
msg1 = c1(1);
c1(1) = [];
disp("received " + msg1);
elseif ~isempty(c2) then
msg2 = c2(1);
c2(1) = [];
disp("received " + msg2);
end
end
endfunction
// Run the example
tic();
select_example();
execution_time = toc();
disp("Execution time: " + string(execution_time) + " seconds");In this Scilab implementation, we use arrays (c1 and c2) to simulate channels. The parallel_run function is used to start parallel executions, similar to goroutines. We use a polling mechanism to check for new values in our “channels”.
To run the program, save it as select_example.sce and execute it in Scilab:
--> exec('select_example.sce', -1)
received one
received two
Execution time: 2.0101 secondsWe receive the values “one” and then “two” as expected. Note that the total execution time is only about 2 seconds since both the 1 and 2 second delays execute concurrently.
This example demonstrates how to implement concurrent operations and synchronization in Scilab, even though it doesn’t have built-in support for channels or select statements like some other languages.