Changeset 794 in lmdz_wrf

Timestamp:

Jun 1, 2016, 4:18:16 PM (9 years ago)

Author:

lfita

Message:

Adding significant_decomposition: Function to decompose a given number by its signifcant potencies

File:

• trunk/tools/generic_tools.py (modified) (1 diff)

trunk/tools/generic_tools.py

@@ -6323 +6323 @@
     return ni,xi,nj,xj
 
+def significant_decomposition(num,minpot):
+    """ Function to decompose a given number by its signifcant potencies
+      returns: [numPot], [Potlist], [Diglist]
+        [numPot]: number of potencies
+        [Potlist]: list of potencies
+        [Diglist]: list of digits
+        Thus:
+          num <> np.sum([Diglist]*10.**[Potlist])
+
+      num= number to decompose
+      minpot= minumum potence to decompose
+    >>> significant_decomposition(np.pi,5)
+    7, [0.0, -1.0, -2.0, -3.0, -4.0, -5.0, -6.0], [3, 1, 4, 1, 5, 9, 2]
+    """
+    fname = 'significant_decomposition'
+
+    potencies = []
+    potval = []
+
+    anum = np.abs(num)
+    diff = anum*1.
+    iipot = 1
+    while diff > 0.:
+        pot = np.floor(np.log10(diff))
+        potv = np.int(diff/(10.**pot))
+#        print 'Lluis:',np.log10(diff), pot,':',10.**pot,':',diff/(10.**pot),'.',potv,'.',potv*10.**pot,diff
+        diff = diff - potv*10.**pot
+        potencies.append(pot)
+        potval.append(potv)
+        if pot < -minpot: break
+        iipot = iipot + 1
+
+    return iipot, potencies, potval