MacWorld 1999 March

home *** CD-ROM | disk | FTP | other *** search

/ MacWorld 1999 March - Disc 1 / Macworld (1999-03) (Disk 1).dmg / Shareware World / Maths & Science / YaCa151 / ReadMe < prev next >

Wrap

Text File | 1999-01-07 | 10.7 KB | 361 lines | [TEXT/ttxt]

——————————————————————————————————————————————————————————————————————————— YaCa 1.5.1 Simon Richardson 1999 http://www.cobalt.u-net.com ——————————————————————————————————————————————————————————————————————————— CONTENTS 1 ENVIRONMENT BUTTONS and the KEYBOARD 2 NUMBERS OPERATIONS FUNCTIONS 3 CLEAR UNDO/REDO MEMORY COPY and PASTE 4 CONVERSIONS 5 PREFERENCES ——————————————————————————————————————————————————————————————————————————— 1.1 ENVIRONMENT Requires System 7.0 or later. Any mac with at least a 68020 processor. 170k of free ram. Prefers Colour. 1.2 BUTTONS and the KEYBOARD The calculator can be driven by clicking the buttons or from the keyboard. Hold down the shift key while you click a button or press a key to get the alternative function shown above it. Key Equivalent Button --- ----------------- <e> exponent <enter> = <delete> clear <clear> clear <s> sin <c> cos <t> tan <k> constant (pi and e) <l> log <n> ln <q> sqr root <r> 1/x <f> change sign <p> power <i> memory in (store) <o> memory out (recall) and brackets [ ]. ——————————————————————————————————————————————————————————————————————————— 2.1 NUMBERS Use the Display submenu on the Edit menu to choose how numbers are displayed. - ‘General’ shows up to 10 significant digits. - ‘Exponential’ shows numbers in exponential format at all times. General will switch to exponential format if a number gets too big. In either mode an exponent can be entered using the <exp> button or the <e> key. 2e2 means 2 times ten to the 2, that is; 200 2e-3 means 0.002 Exponents are always integers. Results that are too big are displayed as ‘INF’ (infinity). 2.2 OPERATIONS There is a precedence of operators which means that operations are not performed left to right but according to their 'precedence': ^ exponentiation is performed first * / multiplication and division are performed next + - addition and subtraction are performed last So expressions are evaluated as they are conventionally written: 10 * 2 + 3 = means (10 * 2) + 3 = 23 10 + 2 * 3 = means 10 + (2 * 3) = 16 10 * 2 ^ 3 = means 10 * (2 ^ 3) = 80 You can use brackets to change the order of evaluation. Brackets can be nested 9 deep. 10 * 2 + 5 = 25 10 * (2 + 5) = 70 + and - can be applied monadically like this: 2 + -1 = 1 10 * -(2 + 5) = -70 Percentage is a variation on '=', it evaluates x = y*(x/100) first. In practice it's used like this: 50 + 10 %= 55 50 - 10 %= 45 50 * 10 %= 250 Remember that precedence of operators still applies here: 50 + 50 * 10 %= is 50 + (50 * 5) is 50 + 250 = 300 Finally, this is unusual but possible: 2 ^ 400 %= is 2 ^ 8 = 256 2.3 FUNCTIONS Most functions are obvious and work like other calculators, in other words they are NOT used as you would write them down. They have the highest precedence and are evaluated immediately: 7 + 9 √ = means 7 + 'square root of' 9 which is 7 + 3 = 10 ( 7 + 9 ) √ = means 'square root of' (7 + 9) which is 16 √ = 4 Similarly, to find 10 sin(30°) enter... 30 sin * 10 = or... 10 * ( 30 sin ) = Trigonometric functions interpret angles as radians or degrees depending on the setting on the Edit-Angles menu. An angle can be converted between radians and degrees at any time using the Convert menu. Note; factorial is an integer function, but if you ask for the factorial of a real number, the calculator will (1) make it positive and (2) round it down to the nearest integer, so: 2.3! is evaluated as 2! -6.8! is evaluated as 6! The maximum factorial allowed is 1700! ( = a very big number). ——————————————————————————————————————————————————————————————————————————— 3.1 CLEAR Plain clear <C> clears x, so if you make a mistake you can correct it; 100 + 200 <C> 300 = evaluates as 100 + 300 = Shift clear <AC> means all clear, it clears everything except the memory. If you have pressed the wrong button and want to clear a single digit you should use Undo... 3.2 UNDO/REDO Undo undoes the last action performed. It completely reverses the action, restoring the calculator to the state it was in before the action. Once undone, an action can be re-done by selecting Redo. The following actions are undoable: - Digits, Constants - Operators and Functions - Clear (but not All Clear) - Equals - Memory, Push and Pop - Brackets - Conversions - Paste The following cannot be undone: - Copy and Cut - All Clear The following are not affected by undo, and do not affect it: - Altering preferences. - Altering angle or display modes. Undo/Redo can be selected from the keyboard with command Z. 3.3 MEMORY Memories are saved when you quit (which is why they appear on the File menu). Accessing 'm' The memory can be accessed using these buttons; STO store x in the memory RCL recall x from the memory m+x add x to the memory m*x multiply the memory by x Accessing the 'k' memories There are 9 extra memories known as k1 to k9. To access them use the STO or RCL buttons with the shift key held down, then enter a digit to specify which memory you want: <shift>STO 5 stores x in k5 Seeing the memories Store and Recall are also available on the File menu. The contents of all the memories are displayed here. Push and Pop This is advanced stuff, pushing and popping a stack is common in programming but may be a strange idea elsewhere. The k memories can treated as a stack. Imagine all the k memories as a continous block with k1 at the top and k9 at the bottom. <Push> makes the contents of each k memory move downwards: k1 moves to k2, k2 moves to k3, and so on, with k9 falling off the bottom. The value of x is copied onto the top at k1. <Pop> does the reverse. k1 is copied to x, then all the values move upwards, with k9 at the bottom being filled with 0. The easiest way to get the hang of it is experiment; put a value in x, press <push> and then have a look at the memories under the File menu. Push a few more values to see the stack moving downwards, then try popping. It is important to remember that every time you push, k9 falls off the bottom and is lost forever. Remember too that the basic memory 'm' is not affected by pushing or popping. 3.4 COPY and PASTE Cut, Copy and Clear are enabled whenever the displayed number is not 0. Paste is enabled whenever there is text to paste that is a number. Clear on the menu is the same as pressing the clear button. ——————————————————————————————————————————————————————————————————————————— 4.1 CONVERSIONS Most of the conversions are worked out from first principle and are exact (to the limit of displayed digits). For example, the inch is defined internationally to be exactly 25.4mm. Where approximations are used they are to at least 8 significant digits. Approximate conversions are indicated by the -÷> dotted arrow symbol. Angles Conversions between radians and degrees work at any time, the Edit-Angles menu only affects trig functions as they are used. Distance - Miles are statute miles, equal to 5280 feet. - Nautical miles are international standard nautical miles (1852 metres). - A fathom is an (old) unit of depth, equal to six feet. - Points are set in the preference dialog (see 5.1 below). A pica is 12 points. Mass - Units like the ounce are both imperial and US. - A tonne is 1000 kg, or a 'megagramme'. - UK measures are also known as Avoirdupois. - UK cwt and tons are also known as 'long' (1 cwt = 112 lb). - US cwt and tons are also known as 'short' (1 cwt = 100 lb). Time - ... Area - Hectares are rather trivial to convert but are the standard measure of land, 1 hectare = 100 ares, or 1/100th of a sq km. Volume - The SI unit is the cubic metre, but the more practical litre is used here, 1 cu metre = 1000 litres, or 1 litre = 1 cu decimetre - There are two varieties of US measure; dry and liquid (wet). The liquid measures are the most common. - A barrel of oil is an international unit, but is under 'US' because it happens to be exactly 42 US wet gallons. Speed - Knots are nautical miles per hour (see distance). Force - 1 kgF is the force exerted by 1 kilogramme under 1 Standard Earth Gravity. - 1 Standard Earth Gravity is defined to be 9.80665 [m/s2] exactly. Pressure - The basic unit is the Pascal which equals 1 newton per sq metre. This is a very small pressure, kiloPascals [kPa] and even megaPascals [MPa] are more common. Temperature - Temperatures below absolute zero (0°K) are treated as potential errors. Recommended web sites for information on units and conversions. Concise, comprehensive and accurate data: A Dictionary of Units <http://www.ex.ac.uk/cimt/dictunit/dictunit.htm> Detailed history and background information: How Many? <http://www.unc.edu/~rowlett/units/index.html> ——————————————————————————————————————————————————————————————————————————— 5.1 PREFERENCES At the bottom of the Edit menu there are three items: Display, Angles and Preferences. These allow various options to be set. The settings are saved when you quit. Display offers general or exponential display in the LCD. Angles affects the way angles are interpreted by trig functions. In the Preferences dialog: Points affects conversions. For general typographic work with applications such as Photoshop or Pagemaker use DTP points (72 per inch). Didot and traditional points are very rare nowadays. Sounds can be loud, soft or off. Loud is slightly less than the general volume level set in the Sound control panel, soft is about half that. If Title is checked a title appears in the bar at the top of the calculator. This is useful if you collapse the window using WindowShade, or System 8. ——————————————————————————————————————————————————————————————————————————— // end of file