Old School Calculator
Old School Calculator is a scientific calculator doing plain and simple math. Just input a formula as you would write it down.
The calculator comes with decimal, sexagesimal, exponential and fractional displays. It performs arithmetic, trigonometric and logarithmic functions. It knows about permutations, combinations and coordinate conversion.
...and it stores up to 7 numerical results!
Really simple input
Old School Calculator knows about precedence rules.
Example: 10 + 2×6 - 15 ÷ (1 + 2) = 17
| input |
display |
|
1
0
+
|
10. +
|
|
2
×
6
-
|
22. -
|
|
1
5
÷
(
|
( 0.
|
|
1
+
2
)
|
3.
|
|
=
|
= 17.
|
The following examples use a shorter notation.
Instead of
10.25 you would type
1
0
.
2
5.
Old School Calculator accepts algebraic (infix) and old-style input methods. You can set the input method to be used on the settings page (gear in the top right corner).
An example with algebraic (infix) input method: √2 ÷ cos -45° = 2
√
2
÷
cos
45
+/-
=
= 2.
The same example with old-style input method: √2 ÷ cos -45° = 2
2
√
÷
45
+/-
cos
=
= 2.
Number input
| Category |
Example |
|
Input |
| rational numbers |
0.3 |
|
.
3 or
0
.
3
|
| negative numbers |
-4.7 |
|
4.7
+/-
|
| exponential notation |
3×10
2
|
(=300) |
3
EXP
2
|
|
-5.2×10
3
|
(=-5200) |
5.2
+/-
EXP
3
|
|
-8.3×10
-4
|
(=-0.00083) |
8.3
+/-
EXP
4
+/-
|
| pi |
π |
(=3.141592653...) |
EXP
|
| fractions |
2/3 |
(=0.666666...) |
2
a b/c
3
|
|
5 1/4 |
(=5.25) |
5
a b/c
1
a b/c
4
|
| degrees |
5° 20' 30" |
(=5.341666...) |
5
° ' "
20
° ' "
30
° ' "
|
Functions 1
argument
function
For these functions you enter the argument followed by the function key.
|
Function |
Example |
Input |
Display |
|
1/x
|
Reciprocal |
2
-1 = 0.5
|
2
1/x
=
|
0.5
|
|
x
2
|
Square |
3
2 = 9
|
3
x
2
=
|
9.
|
|
x!
|
Factorial |
3! = 6 |
3
SHIFT
x!
=
|
6.
|
Functions 2
Old School Calculator comes with 2 input methods: algebraic (infix) and old-style. You can set the input method to be used on the settings page (gear in top right corner).
algebraic (infix) input method
function
argument
Modern scientific calculators often use algebraic (infix) input method.
For these functions you press the function key followed by the argument if the input method is set to algebraic (infix).
|
Function |
Example |
Display |
|
√
|
Square root |
√9 = 3
√
9
=
|
3.
|
|
3√
|
Cube root |
3√27 = 3
SHIFT
3√
27
=
|
3.
|
|
log
|
Common logarithm |
log 100 = 2
log
100
=
|
2.
|
|
10
x
|
Powers of 10 |
10
2 = 100
SHIFT
10
x
2
=
|
100.
|
|
ln
|
Natural logarithm |
ln 10 = 2.302585093
ln
10
=
|
2.302585093
|
|
e
x
|
Powers of e |
e
2.302585093 = 10
SHIFT
e
x
2.302585093
=
|
10.
|
sin
cos
tan
|
Sine, cosine, tangent |
sin 30° = 0.5
sin
30
=
|
0.5
|
sin
-1
cos
-1
tan
-1
|
Arc
sine, cosine, tangent
|
asin 0.5 = 30°
SHIFT
sin
-1
.5
=
|
30.
|
hyp
sin
hyp
cos
hyp
tan
|
Hyperbolic
sine, cosine, tangent
|
sinh 5 = 74.20321058
hyp
sin
5
=
|
74.20321058
|
hyp
sin
-1
hyp
cos
-1
hyp
tan
-1
|
Inverse hyperbolic
sine, cosine, tangent
|
sinh
-1 74.20321058 = 5
SHIFT
hyp
sin
-1
74.20321058
=
|
5.
|
old-style input method
argument
function
Older, more basic calculators often use this input method.
For these functions you enter the argument first and then press the function key if the old-style input method is set.
|
function |
example |
display |
|
√
|
Square root |
√9 = 3
9
√
=
|
3.
|
|
3√
|
Cube root |
3√27 = 3
27
SHIFT
3√
=
|
3.
|
|
log
|
Common logarithm |
log 100 = 2
100
log
=
|
2.
|
|
10
x
|
Powers of 10 |
10
2 = 100
2
SHIFT
10
x
=
|
100.
|
|
ln
|
Natural logarithm |
ln 10 = 2.302585093
10
ln
=
|
2.302585093
|
|
e
x
|
Powers of e |
e
2.302585093 = 10
2.302585093
SHIFT
e
x
=
|
10.
|
sin
cos
tan
|
Sine, cosine, tangent |
sin 30° = 0.5
30
sin
=
|
0.5
|
sin
-1
cos
-1
tan
-1
|
Arc
sine, cosine, tangent
|
asin 0.5 = 30°
.5
SHIFT
sin
-1
=
|
30.
|
hyp
sin
hyp
cos
hyp
tan
|
Hyperbolic
sine, cosine, tangent
|
sinh 5 = 74.20321058
5
hyp
sin
=
|
74.20321058
|
hyp
sin
-1
hyp
cos
-1
hyp
tan
-1
|
Inverse hyperbolic
sine, cosine, tangent
|
sinh
-1 74.20321058 = 5
74.20321058
SHIFT
hyp
sin
-1
=
|
5.
|
Functions with two arguments
argument 1
function
argument 2
|
function |
example |
display |
|
x
y
|
Powers |
2
3 = 8
2
x
y
3
=
|
8.
|
|
x√
|
Roots |
7√128 = 2
7
SHIFT
x√
128
=
|
2.
|
|
nPr
|
Permutations |
6 nPr 3 = 120
6
SHIFT
nPr
3
=
|
120.
|
|
nCr
|
Combinations |
6 nCr 3 = 20
6
SHIFT
nCr
3
=
|
20.
|
|
R→P
|
Rectangular to polar
coordinate conversion
|
x=3, y=4: 3 RP 4 = 5 (r), 53.13010235 (θ)
3
SHIFT
R→P
4
=
|
r = 5.
|
|
|
SHIFT
x ↔ y
|
θ = 53.13010235
|
|
P→R
|
Polar to rectangular
coordinate conversion
|
r=2, θ=60: 2 PR 60 = 1 (x), 1.732050808 (y)
2
SHIFT
P→R
60
=
|
x = 1.
|
|
|
SHIFT
x ↔ y
|
y = 1.732050808
|
Percentage calculations
You can set the kind of percentage calculation to be used on the settings page (gear in top right corner).
Percentage calculations - advanced
Modern scientific calculators often use this kind of percentage calculation. The advanced percentage calculation answers several questions easily.
19% of 120 = 22.8
120
×
19
SHIFT
%
22.8
Percentage of 80 represented by 25 = 31.25%
25
÷
80
SHIFT
%
31.25
19% add-on of 120 = 142.8
120
×
19
SHIFT
%
+
142.8
30% discount of 1000 = 700
1000
×
30
SHIFT
%
-
700.
20 apples are added to a basket with 50 apples. What is the percentage of the new number of apples to the initial number of apples?: 140%
20
+
50
SHIFT
%
140.
If you got 50 EUR last week and 80 EUR this week, what is the percent increase?: 60%
80
-
50
SHIFT
%
60.
Percentage calculations - simple
Basic calculators come often with this kind of percentage calculation.
| example |
input |
display |
| 200 + 19% = 238 |
200
+
19
SHIFT
%
=
|
238.
|
| 238 - 19% = 192.78 |
238
-
19
SHIFT
%
=
|
192.78
|
| 200 ÷ 50% = 2 |
200
÷
50
SHIFT
%
=
|
2.
|
| 200 × 50% = 20000 |
200
×
50
SHIFT
%
=
|
20000.
|
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History
Version 2.1
App Store 2011-07-15, Android Market 2011-08-14, BlackBerry App World 2011-08-18, webOS 2011-08-27.
- new: improber fractions.
- new Android: uses menu key and back key.
- new Android: changed icon.
- fix: random number, 3rd root.
Version 2.0
App Store 2011-03-30, Android Market 2011-03-28.
- new: beautiful math display using the power of TeX (iPad iOS 4.2+, Android tablets 1280x768).
- new: polar and rectangular coordinate conversion.
- new: register exchange.
- new: optimized for Android tablets.
Version 1.5.2
App Store 2011-02-22.
- new: inserts multiplication sign automatically: "4" "sin" => "4 × sin".
- fixed bugs: fractions and degrees display.
Version 1.5.1
App Store 2011-01-21, Android Market 2011-01-29.
- fixed bug: help opens in new window.
- fixed bug: key click for all keys.
Version 1.5
App Store 2011-01-18.
- new: algebraic (infix) and old-style input methods.
- new: simple and advanced percentage calculations.
- improved display.
- new: user guide.
- new: feedback form.
Version 1.4
App Store 2010-11-28.
- new: key clicks.
- changes for iOS 4.2
Version 1.3
App Store 2010-11-04.
- new: Shows entered expressions.
- improved display.
Version 1.2
App Store 2010-10-19.
Version 1.1
Android Market 2010-10-06.
- iPhone, iPad, Android
- new: RND, RAN#, percentage calculations, ENG, ENG-1
Version 1.0
App Store 2010-10-09.
- initial version.
- iPad only.
|
