Reduce array sizes in memory-intensive tests for WASM

WASM has limited linear memory that doesn't grow well under pressure.
Reduce test array sizes to avoid out-of-memory crashes:

- SubscriptTest: 400x400 -> 10x10 on WASI
- RandomTest: 100x100x100 (1M elements) -> smaller arrays on WASI

These changes only affect WASI builds; native builds keep original sizes.

Author: pedrovgs

Tests/MatftTests/RandomTest.swift

@@ -11,32 +11,47 @@ import Matft
 
 final class RandomTests: XCTestCase {
     func testRand() {
-        let a = Matft.random.rand(shape: [100, 100, 100])
+        // Use smaller array size on WASM to avoid memory pressure
+        // 100x100x100 = 1M elements = 4MB per array, too much for WASM
+        #if os(WASI)
+        let shape = [10, 10, 10]  // 1K elements
+        #else
+        let shape = [100, 100, 100]  // 1M elements
+        #endif
+
+        let a = Matft.random.rand(shape: shape)
         let mean_a = a.mean().scalar as! Float
         let cond_a = (Float(0.48) < mean_a) && (mean_a < Float(0.52))
-        
-        let b = Matft.random.rand(shape: [100, 100, 100])
+
+        let b = Matft.random.rand(shape: shape)
         let mean_b = b.mean().scalar as! Float
         let cond_b = (Float(0.48) < mean_b) && (mean_b < Float(0.52))
-        
+
         XCTAssertTrue(cond_a, "The result may be failure due to random generation")
         XCTAssertTrue(cond_b, "The result may be failure due to random generation")
-        
+
         XCTAssertNotEqual(a, b,"The result may be failure due to random generation")
     }
-    
+
     func testRandint() {
-        let a = Matft.random.randint(low: 0, high: 10, shape: [100, 100, 100])
+        // Use smaller array size on WASM to avoid memory pressure
+        #if os(WASI)
+        let shape = [10, 10, 10]  // 1K elements
+        #else
+        let shape = [100, 100, 100]  // 1M elements
+        #endif
+
+        let a = Matft.random.randint(low: 0, high: 10, shape: shape)
         let mean_a = a.mean().scalar as! Float
         let cond_a = (Float(4.48) < mean_a) && (mean_a < Float(4.52))
-        
-        let b = Matft.random.randint(low: 0, high: 10, shape: [100, 100, 100])
+
+        let b = Matft.random.randint(low: 0, high: 10, shape: shape)
         let mean_b = b.mean().scalar as! Float
         let cond_b = (Float(4.48) < mean_b) && (mean_b < Float(4.52))
-        
+
         XCTAssertTrue(cond_a, "The result may be failure due to random generation")
         XCTAssertTrue(cond_b, "The result may be failure due to random generation")
-        
+
         XCTAssertNotEqual(a, b,"The result may be failure due to random generation")
     }
 }

Tests/MatftTests/SubscriptTest.swift

@@ -651,16 +651,22 @@ final class SubscriptTests: XCTestCase {
         }
 
         do{
-            let a = Matft.arange(start: 0, to: 160000, by: 1, shape: [400, 400])
-            let c = MfArray([true]).broadcast_to(shape: [400, 400])
+            // Use smaller array size on WASM to avoid memory pressure
+            #if os(WASI)
+            let size = 10
+            #else
+            let size = 400
+            #endif
+            let a = Matft.arange(start: 0, to: size * size, by: 1, shape: [size, size])
+            let c = MfArray([true]).broadcast_to(shape: [size, size])
             /*
             self.measure {
                 a[c] = MfArray([555])
                 // time in release mode
                 // average: 0.005, relative standard deviation: 8.334%, values: [0.006032, 0.004685, 0.004630, 0.005293, 0.004738, 0.004789, 0.004905, 0.005056, 0.004624, 0.004729],
             }*/
             a[c] = MfArray([555])
-            XCTAssertEqual(a, MfArray([555]).broadcast_to(shape: [400, 400]))
+            XCTAssertEqual(a, MfArray([555]).broadcast_to(shape: [size, size]))
         }