class: center, middle  <!-- Do not forget to adapt the presentation title in the header! --> <!-- Adjust the presentation to the session. Focus on the challenges, this is not a coding tutorial. Note, to include figures, store the image in the `/docs/assets/images` folder and use the jekyll base.url reference as done in this template or see https://jekyllrb.com/docs/liquid/tags/#links. using the scale attribute , you can adjust the image size. --> <!-- Adjust the day, month --> # 23 APRIL 2019 ## INBO coding club <!-- Adjust the room number and name --> Herman Teirlinck<br> 01.70 - Ferdinand Peters --- class: center, middle <!-- Create a new badge using Inkscape based on the assets/images/coding_club_badges.svg file -->  --- class: center, middle <br /> [`dplyr` cheatsheet](https://github.com/inbo/coding-club/blob/master/cheat_sheets/20181129_cheat_sheet_data_transformation.pdf) --- class: center, middle ### How to get started? Check the [Each session setup](https://inbo.github.io/coding-club/gettingstarted.html#each-session-setup) to get started. ### First time coding club? Check the [First time setup](https://inbo.github.io/coding-club/gettingstarted.html#first-time-setup) section to setup. --- class: center, middle  --- class: center, middle ### Share your code during the coding session! <!-- Create a new hackmd file and replace this link (twice!) --> Go to https://hackmd.io/f_obNpkVSRedTcb19kP8Og <iframe src="https://hackmd.io/f_obNpkVSRedTcb19kP8Og" height="400px" width="800px"></iframe> --- background-image: url(/assets/images/background_challenge_1.png) class: left, middle # Challenge 1 - Click [`20190423/20190423_species.csv`](https://github.com/inbo/coding-club/blob/master/data/20190423/20190423_species.csv) and download* data file to `./data` folder. - Click [`20190423/20190423_challenges.R`](https://github.com/inbo/coding-club/blob/master/src/20190423/20190423_challenges.R) and download* script in `./src` folder. <small>* __Note__: check the getting started instructions on [how to download a single file](https://inbo.github.io/coding-club/gettingstarted.html#each-session-setup)</small> - Open the [`20190423/20190423_challenges.R`](https://github.com/inbo/coding-club/blob/master/src/20190423/20190423_challenges.R) file. - Extract the columns: `scientificName, decimalLatitude, decimalLongitude, coordinateUncertaintyInMeters, eventDate, year, identifiedBy, speciesKey and issue` for the observations... - observed in June - from either `Lycopus europaeus`, `Phragmites australis`, `Cymatia bonsdorffi` or `Lemna minor` - where column `issue` is `NA` --- background-image: url(/assets/images/background_challenge_2.png) class: left, middle # Challenge 2 - In the `occs` data.frame, create a new column, called `grid_resolution_km`, by calculating the grid resolution based on the `coordinateUncertaintyInMeters` information. To get the grid resolution from the uncertainty in meter use the following: `gridresolution = sqrt(2) * coordinateUncertaintyInMeters/1000` - Sort the columns from newest to oldest observation --- background-image: url(/assets/images/background_challenge_3.png) class: left, middle # Challenge 3 - In the `occs` data.frame, how many observations (count the number of rows) are available _for each_ year? --- background-image: url(/assets/images/background_challenge_3.png) class: left, middle # Challenge 3 - BONUS - Click [`20180222/20180222_surveys.csv`](https://github.com/inbo/coding-club/blob/master/data/20180222/20180222_surveys.csv) and download data file to `./data` folder. - Calculate the median weight, mean weight and number of records _for each_ identifier in the `species_id` column <small>* __Note__: check the getting started instructions on [how to download a single file](https://inbo.github.io/coding-club/gettingstarted.html#each-session-setup)</small> --- class: center, middle <!-- Always try to include some type of reviewing (can be short and entertaining). Remove this slide if no reviewing is included -->  --- class: center, middle  <!-- Adjust the room and date --> Room: Herman Teirlinck - 01.70 - Frans Breziers<br> Date: __23/05/2019__, van 10:00 tot 12:00<br> (registration announced via DG_useR@inbo.be)