Example User ID lookup

example.php

<?php

// Set the user that you wish to load to one passed via qs, if not, default to logged in user id
$user_id = ( false === isset( $_GET[ 'user-id' ] ) ) ? (int) $_GET[ 'user-id' ] : get_current_user_id();

// Worth checking that the user we're trying to view exists
if ( false === get_userdata( $user_id ) ) {
    // display error saying user doesn't exist
}  

if ( false === does_user_have_permission_to_view( $user_id, get_current_user_id() ) {
    // display error saying this person can't view that person's data
}

bmi_component_gravity_view( $user_id );
bmi_component_wt_start_weight( $user_id );

function bmi_component_wt_start_weight( $user_id = NULL ) {

  if ( true === empty( $user_id ) ) {
     $user_id = get_current_user_id();
  }
  
  // Where possible, call PHP functions directly over the do_shortcode() method, e.g.
  // note: if doing this, worth doing a function_exists() call to ensure the relevant plugin is still enabled.
  
  echo ws_ls_shortcode_start_weight( $user_id );
}

function bmi_component_gravity_view( $user_id = NULL ) {

  if ( true === empty( $user_id ) ) {
     $user_id = get_current_user_id();
  }
  
  $shortcode = sprintf( '[gravityview id="9201" searchfield="user_id" search_value="%d"]', $user_id );
  do_shortcode( $shortcode );
}