Merge pull request #276 from fastai/fix-sparkline

add ceil to make mx and mn work in sparkline

Author: Hamel Husain

fastcore/xtras.py

@@ -242,10 +242,12 @@ def truncstr(s:str, maxlen:int, suf:str='…', space='')->str:
 spark_chars = '▁▂▃▅▆▇'
 
 # Cell
-def _sparkchar(x, mn, incr, empty_zero):
+def _ceil(x, lim=None): return x if (not lim or x <= lim) else lim
+
+def _sparkchar(x, mn, mx, incr, empty_zero):
     if x is None or (empty_zero and not x): return ' '
     if incr == 0: return spark_chars[0]
-    res = int((x-mn)/incr-0.5)
+    res = int((_ceil(x,mx)-mn)/incr-0.5)
     return spark_chars[res]
 
 # Cell
@@ -254,7 +256,7 @@ def sparkline(data, mn=None, mx=None, empty_zero=False):
     valid = [o for o in data if o is not None]
     if not valid: return ' '
     mn,mx,n = ifnone(mn,min(valid)),ifnone(mx,max(valid)),len(spark_chars)
-    res = [_sparkchar(o,mn,(mx-mn)/n,empty_zero) for o in data]
+    res = [_sparkchar(x=o, mn=mn, mx=mx, incr=(mx-mn)/n, empty_zero=empty_zero) for o in data]
     return ''.join(res)
 
 # Cell

nbs/03_xtras.ipynb

@@ -618,7 +618,7 @@
     {
      "data": {
       "text/plain": [
-       "['g', 'a', 'f', 'c', 'e', 'd', 'h', 'b']"
+       "['g', 'e', 'b', 'd', 'a', 'f', 'h', 'c']"
       ]
      },
      "execution_count": null,
@@ -1249,7 +1249,7 @@
     {
      "data": {
       "text/plain": [
-       "Path('.ipynb_checkpoints')"
+       "Path('hamel.py')"
       ]
      },
      "execution_count": null,
@@ -1283,7 +1283,7 @@
     {
      "data": {
       "text/plain": [
-       "(Path('../fastcore/net.py'), Path('03a_parallel.ipynb'))"
+       "(Path('../fastcore/xtras.py'), Path('08_script.ipynb'))"
       ]
      },
      "execution_count": null,
@@ -1400,10 +1400,12 @@
    "outputs": [],
    "source": [
     "#export\n",
-    "def _sparkchar(x, mn, incr, empty_zero):\n",
+    "def _ceil(x, lim=None): return x if (not lim or x <= lim) else lim\n",
+    "\n",
+    "def _sparkchar(x, mn, mx, incr, empty_zero):\n",
     "    if x is None or (empty_zero and not x): return ' '\n",
     "    if incr == 0: return spark_chars[0]\n",
-    "    res = int((x-mn)/incr-0.5)\n",
+    "    res = int((_ceil(x,mx)-mn)/incr-0.5)\n",
     "    return spark_chars[res]"
    ]
   },
@@ -1419,7 +1421,7 @@
     "    valid = [o for o in data if o is not None]\n",
     "    if not valid: return ' '\n",
     "    mn,mx,n = ifnone(mn,min(valid)),ifnone(mx,max(valid)),len(spark_chars)\n",
-    "    res = [_sparkchar(o,mn,(mx-mn)/n,empty_zero) for o in data]\n",
+    "    res = [_sparkchar(x=o, mn=mn, mx=mx, incr=(mx-mn)/n, empty_zero=empty_zero) for o in data]\n",
     "    return ''.join(res)"
    ]
   },
@@ -1443,6 +1445,33 @@
     "print(f'   with \"empty_zero\": {sparkline(data, empty_zero=True )}')"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "You can set a maximum and minimum for the y-axis of the sparkline with the arguments `mn` and `mx` respectively:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'▂▅▇▇'"
+      ]
+     },
+     "execution_count": null,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "sparkline([1,2,3,400], mn=0, mx=3)"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -1531,8 +1560,8 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "Num Events: 3, Freq/sec: 272.3\n",
-      "Most recent:  ▇▁▁▂▁ 460.5 360.2 359.1 391.6 379.3\n"
+      "Num Events: 7, Freq/sec: 346.2\n",
+      "Most recent:  ▃▇▆▁▆ 320.1 427.2 389.6 208.7 401.4\n"
      ]
     }
    ],