Begin porting LUNAR to python

got much of the structure moved around, but the flow isn't right yet. Probably will refactor to be object-oriented.

59 Lunar LEM Rocket/lunar.bas

@@ -18,7 +18,7 @@
 170 IF T<1E-03 THEN 150
 180 S=T: IF M>=N+S*K THEN 200
 190 S=(M-N)/K
-200 GOSUB 420: IF I<=O THEN 340
+200 GOSUB 420: IF I<=0 THEN 340
 210 IF V<=0 THEN 230
 220 IF J<0 THEN 370
 230 GOSUB 330: GOTO 160
@@ -26,12 +26,12 @@
 250 V=V+G*S: L=L+S
 260 W=3600*V: PRINT "ON MOON AT";L;"SECONDS - IMPACT VELOCITY";W;"MPH" 
 274 IF W<=1.2 THEN PRINT "PERFECT LANDING!": GOTO 440 
-280 IF W<=10 THEN PRINT "GOOD LANDING (COULD RE BETTER)":GOTO 440 
+280 IF W<=10 THEN PRINT "GOOD LANDING (COULD BE BETTER)":GOTO 440 
 282 IF W>60 THEN 300
 284 PRINT "CRAFT DAMAGE... YOU'RE STRANDED HERE UNTIL A RESCUE" 
 286 PRINT "PARTY ARRIVES. HOPE YOU HAVE ENOUGH OXYGEN!" 
 288 GOTO 440
-300 PRINT "SORRY THERE NERE NO SURVIVORS. YOU BLOW IT!"
+300 PRINT "SORRY THERE WERE NO SURVIVORS. YOU BLEW IT!"
 310 PRINT "IN FACT, YOU BLASTED A NEW LUNAR CRATER";W*.227;"FEET DEEP!"
 320 GOTO 440
 330 L=L+S: T=T-S: M=M-S*K: A=I: V=J: RETURN

59 Lunar LEM Rocket/python/lunar.py

@@ -0,0 +1,206 @@
+"""
+LUNAR
+
+Lunar landing simulation
+
+Ported by Dave LeCompte
+"""
+
+PAGE_WIDTH = 64
+
+
+def print_centered(msg):
+    spaces = " " * ((PAGE_WIDTH - len(msg)) // 2)
+    print(spaces + msg)
+
+
+def print_header(title):
+    print_centered(title)
+    print_centered("CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY")
+    print()
+    print()
+    print()
+
+
+def print_instructions():
+    print("THIS IS A COMPUTER SIMULATION OF AN APOLLO LUNAR")
+    print("LANDING CAPSULE.")
+    print()
+    print()
+    print("THE ON-BOARD COMPUTER HAS FAILED (IT WAS MADE BY")
+    print("XEROX) SO YOU HAVE TO LAND THE CAPSULE MANUALLY.")
+    print()
+
+def print_intro():
+    print("SET BURN RATE OF RETRO ROCKETS TO ANY VALUE BETWEEN")
+    print("0 (FREE FALL) AND 200 (MAXIMUM BURN) POUNDS PER SECOND.")
+    print("SET NEW BURN RATE EVERY 10 SECONDS.")
+    print()
+    print("CAPSULE WEIGHT 32,500 LBS; FUEL WEIGHT 16,500 LBS.")
+    print()
+    print()
+    print()
+    print("GOOD LUCK")
+    print()
+
+def show_landing(l, v):
+    w = 3600 * v
+    print("ON MOON AT {l} SECONDS - IMPACT VELOCITY {w} MPH")
+    if w < 1.2:
+        print("PERFECT LANDING!")
+    elif w < 10:
+        print("GOOD LANDING (COULD BE BETTER)")
+    elif w <= 60:
+        print("CRAFT DAMAGE... YOU'RE STRANDED HERE UNTIL A RESCUE")
+        print("PARTY ARRIVES. HOPE YOU HAVE ENOUGH OXYGEN!")
+    else:
+        print("SORRY THERE WERE NO SURVIVORS. YOU BLEW IT!")
+        print("IN FACT, YOU BLASTED A NEW LUNAR CRATER {w*.227:.4f} FEET DEEP!")
+    end_sim()
+
+        
+def update_physics():
+    # line 330
+    elapsed_time += delta_t
+    time_to_prompt -= delta_t
+    m = m - delta_t * k
+    a = i
+    v = j
+    return
+
+def update_burn():
+    # line 420
+    q = delta_t * k / m
+    j = (v +
+         g * delta_t +
+         z * (-q - q*q/2 - q**3/3 - q**4/4 - q**5/5))
+    i = (a -
+         g * delta_t * delta_t/2 -
+         v * delta_t +
+         z * delta_t * (q / 2 +
+                        q ** 2 / 6 +
+                        q ** 3 / 12 +
+                        q ** 4 / 20 +
+                        q ** 5 / 30))
+
+    return q,j,i
+
+def end_sim():
+    print()
+    print()
+    print()
+    print("TRY AGAIN??")
+
+
+def prompt_for_burn():
+    # line 150
+    print("{l}\t{a}\t{int(5280*(a-int(a)))}\t{3600 * v}\t{m-n}")
+    k = input()
+
+def run_simulation():
+    print()
+    print("SEC\tMI + FT\tMPH\tLB FUEL\tBURN RATE")
+    print()
+    
+    elapsed_time = 0
+    a = 120
+    v = 1 
+    m = 33000 # mass of capsule with fuel
+    n = 16500 # mass of capsule without fuel
+    g = 1e-3
+    z = 1.8
+
+    k = prompt_for_burn()
+    time_to_prompt = 10
+
+    while True:
+        # line 160
+        if M-N < 1e-3:
+            # line 240
+            print(f"FUEL OUT AT {elapsed_time} SECONDS")
+            delta_t = (-v + math.sqrt(v*v + 2*a*g)) / g
+            v += g * delta_t
+            elapsed_time += delta_t
+            show_landing(elapsed_time, v)
+            return
+
+        if t < 1e-3:
+            k = prompt_for_burn()
+            continue
+
+        # line 180
+        delta_t = time_to_prompt
+        if m < n + delta_t * k:
+            delta_t = (m-n) / k
+            
+        # line 200
+        q,j,i = update_burn()
+
+        if i <= 0:
+            # line 340
+            while True:
+                if delta_t < 5e-3:
+                    show_landing(elapsed_time, v)
+                #line 350
+                d = v + math.sqrt(v*v + 2*a*(g-z*k/m))
+                delta_t = 2 * a / d
+                update_burn()
+                update_physics()
+
+        else:
+            # line 210
+            if ((v > 0) and (j < 0)):
+                GOTO 370
+            # line 230
+            update_physics()
+
+
+
+        
+        
+
+
+def main():
+    print_header("LUNAR")
+    print_instructions()
+    while True:
+        print_intro()
+        run_simulation()
+        
+
+"""
+120 L=0
+130 PRINT: PRINT "SEC","MI + FT","MPH","LB FUEL","BURN RATE":PRINT 
+140 A=120:V=1:M=33000:N=16500:G=1E-03:Z=1.8
+150 PRINT L,INT(A);INT(5280*(A-INT(A))),3600*V,M-N,:INPUT K:T=10 
+160 IF M-N<1E-03 THEN 240
+170 IF T<1E-03 THEN 150
+180 S=T: IF M>=N+S*K THEN 200
+190 S=(M-N)/K
+200 GOSUB 420: IF I<=O THEN 340
+210 IF V<=0 THEN 230
+220 IF J<0 THEN 370
+230 GOSUB 330: GOTO 160
+240 PRINT "FUEL OUT AT";L;"SECONDS":S=(-V+SQR(V*V+2*A*G))/G
+250 V=V+G*S: L=L+S
+260 W=3600*V: PRINT "ON MOON AT";L;"SECONDS - IMPACT VELOCITY";W;"MPH" 
+274 IF W<=1.2 THEN PRINT "PERFECT LANDING!": GOTO 440 
+280 IF W<=10 THEN PRINT "GOOD LANDING (COULD RE BETTER)":GOTO 440 
+282 IF W>60 THEN 300
+284 PRINT "CRAFT DAMAGE... YOU'RE STRANDED HERE UNTIL A RESCUE" 
+286 PRINT "PARTY ARRIVES. HOPE YOU HAVE ENOUGH OXYGEN!" 
+288 GOTO 440
+300 PRINT "SORRY THERE NERE NO SURVIVORS. YOU BLOW IT!"
+310 PRINT "IN FACT, YOU BLASTED A NEW LUNAR CRATER";W*.227;"FEET DEEP!"
+320 GOTO 440
+330 L=L+S: T=T-S: M=M-S*K: A=I: V=J: RETURN
+340 IF S<5E-03 THEN 260
+350 D=V+SQR(V*V+2*A*(G-Z*K/M)):S=2*A/D
+360 GOSUB 420: GOSUB 330: GOTO 340
+370 W=(1-M*G/(Z*K))/2: S=M*V/(Z*K*(W+SQR(W*W+V/Z)))+.05:GOSUB 420
+380 IF I<=0 THEN 340
+390 GOSUB 330: IF J>0 THEN 160
+400 IF V>0 THEN 370
+410 GOTO 160
+
+"""