# How to ...

### Multicache - creating waypoints

You can type coordinates to note field, select them and convert to waypoint via context menu.

Note How PD works
N 50 41.123 E 15 10.456
50 41.123 15 10.456
50d41.123 15d10.456
“d” or space means degrees, coordinates are read as thery are typed, hemisphere N/S and E/W is optional
41.123 10.456 numbers are seen as minutes, degrees are taken from cache coordinates
123 456 numbers are seen as thousandth of minutes, degrees and whole minutes are taken from cache coordinates

### Azimuth and distance - projection

If the author assigned to cache only the direction and distance PocketDrake will help you determine where to go. The process is simple:

• add waypoint on starting coordinates, where the distance is calculated from
• use the right arrow button to open a dialog box for setting the azimuth and distance
• after tapping OK the original waypoint coordinates are replaced with new ones

### Formula Solver

#### Basics

Two information is necessary to solve a formula

• variables
• formula itself

Variables are usually commot for all waypoints, they are stored in cache note.

There could be more waypoints with different formulas, we store forumlas in waypoint note.

Variables and formulas must me marked with special tags

```<! variables !>
<? formulas ?> ```

#### Formulas steb by step

##### 1. Collect variables and write them into cache note, follow these simple rules:
• name and value is separated by colon or equal sign, example A=1 B:3
• variables must me separated by space or line break
• it is possible to assign more letters at a time, example ABC=456
##### 2. Mark varibales block (it could be only one)
• select block
• coose Mark variables from context menu

##### 5. Add formula to waypoint

(1) Use Paste formulas, PocketDrake adds necessary tags automatically
(2) Adjust formula so that the first line of the formula is for the latitude (N/S) and the other for the longitude (E/W)
(3) Open formula solver tapping Calculate formulas

##### 6. Fine tune formulas

Edit formulas to follow basic syntax rules:

• separately calculated groups of digits are enclosed in square brackets [ ]
• supported math operations are add (+), subtract (-), multiply (*), divide (/), power (^) and round bracket
• priority of operators is respected, ie, first to multiply and divide and then add and subtract

Use the Normalize formulas (1) to simplify edittind:

• replaces outer round brackets with square ones
• moves N/S and W/E to corresponding fields
• removes unnecessary characters

Now, we can try Calculate formulas (2)

##### 7. Calculation

If there is an error in the formula (wrong syntax, the brackets doesn't match, undefined variable), the error message appears in Result box, otherwise there are calculated coordinates. Digit sum (Σ box) is automatically calculated too.