Added support for percentages

Author: JWock82

ipycalc/calc.py

@@ -69,11 +69,13 @@
 kPa = ureg.kilopascal
 MPa = ureg.megapascal
 GPa = ureg.gigapascal
+percent = ureg.percent
+pct = ureg.pct
 
 unit_list = ['inch', 'feet', 'ft', 'mi', 'ozf', 'lbf', 'lbm', 'kip', 'ton', 'tonf', 'plf', 'klf', 'psi', 'psf', 
              'ksi', 'ksf', 'pcf', 'kcf', 'lbin', 'lbft', 'kipin', 'kipft', 'kin', 'kft', 'mph',
              'rpm', 'Hz', 'deg', 'rad', 'sec', 'minute', 'hr', 'gal', 'degF', 'degC', 'mm', 'cm', 'm', 'km', 'N', 'kN', 'kgf', 'tonne', 'tonnef', 'Pa',
-             'kPa', 'MPa', 'GPa']
+             'kPa', 'MPa', 'GPa', 'percent', 'pct']
 
 #%%
 @register_cell_magic
@@ -167,6 +169,8 @@ def sync_namespaces(local_ns):
     local_ns['GPa'] = ureg.gigapascal
     local_ns['tonne'] = ureg.tonne
     local_ns['tonnef'] = ureg.tonnef
+    local_ns['percent'] = ureg.percent
+    local_ns['pct'] = ureg.pct
 
     # Provide the IPython console with access to the `funit` method
     local_ns['funit'] = funit
@@ -209,6 +213,10 @@ def process_line(calc_line, local_ns):
     equation = equation.replace('^prime', '_prime')
     equation = equation.replace('^', '**')
     equation = equation.replace('lambda', 'lamb')
+    
+    # Convert percentage symbols to percent units
+    # Match % symbols that follow numbers/variables (but not in strings)
+    equation = re.sub(r'(\d+(?:\.\d+)?)\s*%', r'\1*percent', equation)
 
     # Resolve prime symbols in the variable before we compare it to the equation, which has already had them resolved
     variable = variable.replace('^prime', '_prime')
@@ -479,15 +487,20 @@ def replace_string(match):
 
     # Provide a space before any units
     text = text.replace('*inch', ' \\ in')
+    
+    # Handle percent specially - use % symbol instead of word
+    text = text.replace('*percent', '\\%')
+    text = text.replace('*pct', '\\%')
     for unit in unit_list:
-        text = text.replace('*' + unit, ' \\ ' + unit)
+        if unit not in ['percent', 'pct']:  # Skip percent as we already handled it
+            text = text.replace('*' + unit, ' \\ ' + unit)
 
     # Replace multiplication symbols in front of numbers with a multiplication dot
     for i in range(10):
         text = text.replace('*' + str(i), '\\cdot{}' + str(i))
 
-    # Remove all other multiplication symbols
-    text = text.replace('*', '')
+    # Convert remaining multiplication symbols to centered dots for better readability
+    text = text.replace('*', '\\cdot{}')
 
     # Return the Latex text
     return text
@@ -688,6 +701,9 @@ def funit(value, precision=None):
         latex_value = str(round(value, precision))
     else:
         latex_value = str(value)
+    
+    # Replace pct unit with % symbol early
+    latex_value = latex_value.replace('pct', '%')
 
     # Step through each character in the value
     for i, char in enumerate(latex_value):
@@ -700,7 +716,10 @@ def funit(value, precision=None):
 
             # The round function tags on a .0 after it rounds floats. It doesn't do it to integers. Correct this.
             if precision == 0:
-                latex_value = latex_value.replace('.0', '')                
+                latex_value = latex_value.replace('.0', '')
+            
+            # Escape the % symbol for LaTeX
+            latex_value = latex_value.replace('%', '\\%')
 
             # Return the formatted value
             return latex_value

ipycalc/ipycalc_en.txt

@@ -155,6 +155,9 @@ count = []
 # Conversion factors are exact (except when noted),
 # although floating-point conversion may introduce inaccuracies
 
+# Dimensionless
+percent = 0.01 = pct
+
 # Angle
 turn = 2 * π * radian = _ = circle
 cycle = 1  # Dimensionless count for frequency (1 cycle = 1 complete oscillation)

test_notebook.ipynb

@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "code",
-   "execution_count": 10,
+   "execution_count": 1,
    "id": "056b8594-3f8a-4fd3-89f5-ee9fdf999752",
    "metadata": {
     "editable": true,
@@ -20,7 +20,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 17,
+   "execution_count": 2,
    "id": "de54315d",
    "metadata": {
     "editable": true,
@@ -217,7 +217,7 @@
        "$\\begin{array}{l l l}\n",
        "\\begin{array}{l} {\\small{\\textsf{Specified Yield Strength: }}} \\end{array}&\\begin{array}{l} {\\small{F_{y}=50 \\ ksi}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{Testing}}} \\\\ {\\small{\\textsf{reference line breaks}}} \\end{array}\\\\ \n",
        "\\begin{array}{l} {\\small{\\textsf{Plastic Section}}} \\\\ {\\small{\\textsf{Modulus: }}} \\end{array}&\\begin{array}{l} {\\small{Z_{x}=15 \\ in^{3}}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{Testing description line breaks}}} \\end{array}\\\\ \n",
-       "\\begin{array}{l} {\\small{\\textsf{Nominal Yield Strength: }}} \\end{array}&\\begin{array}{l} {\\small{M_{y}=F_{y}Z_{x}+}} \\\\ \\hspace{2em} {\\small{0 \\ kft=62 \\  kft}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{Added + 0*kft to test equation line breaks}}} \\end{array}\\\\ \n",
+       "\\begin{array}{l} {\\small{\\textsf{Nominal Yield Strength: }}} \\end{array}&\\begin{array}{l} {\\small{M_{y}=F_{y}\\cdot{}Z_{x}+}} \\\\ \\hspace{2em} {\\small{0 \\ kft=62 \\  kft}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{Added + 0*kft to test equation line breaks}}} \\end{array}\\\\ \n",
        "\\end{array}$"
       ],
       "text/plain": [
@@ -234,11 +234,51 @@
     "Plastic Section\\\\Modulus: Z_x = 15*inch**3 #Testing description line breaks\n",
     "Nominal Yield Strength: M_y = F_y*Z_x +\\\\0*kft -> 0*kft #Added + 0*kft to test equation line breaks"
    ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "bc1ff481",
+   "metadata": {},
+   "source": [
+    "## **Testing Percentages**"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "id": "3cfb5465",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/markdown": [
+       "$\\begin{array}{l l l}\n",
+       "\\begin{array}{l} {\\small{\\textsf{Tax Rate: }}} \\end{array}&\\begin{array}{l} {\\small{tax_{rate}=15\\%=15 \\  \\%}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{}}} \\end{array}\\\\ \n",
+       "\\begin{array}{l} {\\small{\\textsf{Price: }}} \\end{array}&\\begin{array}{l} {\\small{price=100}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{}}} \\end{array}\\\\ \n",
+       "\\begin{array}{l} {\\small{\\textsf{Tax Amount: }}} \\end{array}&\\begin{array}{l} {\\small{tax=price\\cdot{}tax_{rate}=15.0}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{}}} \\end{array}\\\\ \n",
+       "\\begin{array}{l} {\\small{\\textsf{Total: }}} \\end{array}&\\begin{array}{l} {\\small{total=price+tax=115.0}} \\end{array}&\\begin{array}{l} {\\small{\\textsf{}}} \\end{array}\\\\ \n",
+       "\\end{array}$"
+      ],
+      "text/plain": [
+       "<IPython.core.display.Markdown object>"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "%%calc\n",
+    "Tax Rate: tax_rate = 15% -> 3*percent\n",
+    "Price: price = 100\n",
+    "Tax Amount: tax = price * tax_rate -> 2\n",
+    "Total: total = price + tax -> 2"
+   ]
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
+   "display_name": "venv (3.13.11)",
    "language": "python",
    "name": "python3"
   },