test

.gitignore

@@ -35,4 +35,5 @@ lang-sentences*
 /venv310/
 /cmake-build-debug-docker/
 /build-docs/
-.vscode
+/a.out.dSYM/
+a.out

.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+      {
+        "name": "for",
+        "type": "cppdbg",
+        "request": "launch",
+        "preLaunchTask": "ipwr",
+        "program": "${workspaceFolder}/a.out",
+        "args": [],
+        "stopAtEntry": false,
+        "cwd": "${workspaceFolder}",
+        "environment": [],
+        "externalConsole": false,
+        "MIMode": "gdb"
+      },
+    ]
+}

.vscode/tasks.json

@@ -0,0 +1,10 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "type": "shell",
+            "label": "ipwr",
+            "command": "gfortran pdp10/algebra/ipwr.for -g -O0 -fbacktrace -fcheck=all -ffpe-trap=zero,overflow,underflow -Wall -Wextra -Warray-temporaries -Wconversion -ffree-line-length-0",
+        }
+    ]
+}

pdp10/algebra/ipwr.for

@@ -0,0 +1,10 @@
+
+      program hello
+      integer :: i
+      real :: pi
+      pi = 3.1415927
+      i = 0
+      i = i + 1
+      print *, 'Hello, World!', pi
+      end program hello
+

pdp10/algebra/ipwr.py

@@ -1,9 +1,21 @@
-""" imaginary powers of base 10. starting with 10**(i/1024), and squaring successively ten times"""
+""" imaginary powers of base 10. starting with 10**(i/1024), and squaring successively ten times. this matches with feynman's table 22-3"""
 from math import sqrt
+
+# non rounded version
 y = .00225  # should be .0022486
 x = sqrt(1. - y**2)
 for _ in range(11):
     print('%10.7f %10.7f' % (x, y))
     x2 = x**2 - y**2
     y2 = 2 * x * y
     x, y = x2, y2
+
+# rounded version that more closely matches feynman's table 22-3
+y = .00225  # should be .0022486
+x = round(sqrt(1. - y**2), 7)
+for _ in range(11):
+    print('%10.5f %10.5f' % (x, y))
+    x2 = round(x**2 - y**2, 7)
+    y2 = round(2 * x * y, 7)
+    x, y = x2, y2
+