New slices_eval_getitem() for accelerating evals with __getitem__

Author: FrancescAlted

bench/ndarray/slice-expr.py

@@ -0,0 +1,51 @@
+# Imports
+import numpy as np
+import blosc2
+import time
+
+
+file = "dset-ones.b2nd"
+# a = blosc2.open(file)
+# expr = blosc2.where(a < 5, a * 2**14, a)
+d = 200
+shape = (d,) * 4
+chunks = (d // 4,) * 4
+blocks = (d // 10,) * 4
+print(f"Creating a 4D array of shape {shape} with chunks {chunks} and blocks {blocks}...")
+t = time.time()
+#a = blosc2.linspace(0, d, num=d**4, shape=(d,) * 4, blocks=(d//10,) * 4, chunks=(d//2,) * 4, urlpath=file, mode="w")
+#a = blosc2.linspace(0, d, num = d**4, shape=(d,)*4, blocks=(d//10,)*4, chunks=(d//2,)*4)
+# a = blosc2.arange(0, d**4, shape=(d,) * 4, blocks=(d//10,) * 4, chunks=(d//2,) * 4, urlpath=file, mode="w")
+a = blosc2.ones(shape=shape, chunks=chunks, blocks=blocks) #, urlpath=file, mode="w")
+t = time.time() - t
+print(f"Time to create array: {t:.6f} seconds")
+t = time.time()
+#expr = a * 30
+expr = a * 2
+print(f"Time to create expression: {time.time() - t:.6f} seconds")
+
+# dim0
+t = time.time()
+res = expr[1]
+t0 = time.time() - t
+print(f"Time to access dim0: {t0:.6f} seconds")
+
+# dim1
+t = time.time()
+res = expr[:,1]
+t1 = time.time() - t
+print(f"Time to access dim1: {t1:.6f} seconds")
+
+# dim2
+t = time.time()
+res = expr[:,:,1]
+t2 = time.time() - t
+print(f"Time to access dim2: {t2:.6f} seconds")
+
+# dim3
+t = time.time()
+res = expr[:,:,:,1]
+#res = expr[1]
+t3 = time.time() - t
+
+print(f"Time to access dim3: {t3:.6f} seconds")